What common error(s) did this student make? What is the correct solution for x? Please help

What Common Error(s) Did This Student Make? What Is The Correct Solution For X? Please Help

Answers

Answer 1

Answer:

10x - 5(x - 1) = 20

10x - 5x + 5 = 20

5x + 5 = 20

5x = 20 - 5

5x = 15

x = 15/5

x = 3

Step-by-step explanation:

Answer 2

Answer:

x = 3

Step-by-step explanation:

The first error was in the 2nd line:  -5(x - 1) is -5x + 5, not -5x - 5 = 20.

Continuing the solution:

10x - 5x + 5 = 20

Combining like terms, we get

5x = 15, and so x = 3


Related Questions

what is the image of (8,-1) after a reflection over the line y=x

Answers

Answer:

(- 1, 8 )

Step-by-step explanation:

Under a reflection in the line y = x

a point (x, y ) → (y, x ) , thus

(8, - 1 ) → (- 1, 8 )

The image of (8, -1) after a reflection over the line y = x is, (- 1, 8).

What is Coordinates?

A pair of numbers which describe the exact position of a point on a cartesian plane by using the horizontal and vertical lines is called the coordinates.

We have to given that;

A point (8, - 1) is reflected over the line y = x.

Now, We know that;

The image of point (x, y) after reflection over the line y = x is,

⇒ (x, y) → (y, x)

Thus, The image of (8, -1) after a reflection over the line y = x is,

⇒ (8, - 1) → (- 1, 8)

Learn more about the coordinate visit:

https://brainly.com/question/24394007

#SPJ5

what is this −n+(−4)−(−4n)+6

Answers

Answer:

3n + 2

Step-by-step explanation:

[tex]−n+(−4)−(−4n)+6[/tex]

Open the parentheses

[tex] - n - 4 + 4n + 6 \\ [/tex]

Add similar elements

[tex] - n + 4n - 4 + 6 \\ 3n + 2 \\ [/tex]

Answer:

[tex] - n + 6[/tex]

Step-by-step explanation:

[tex] - n + ( - 4) - ( - 4n) + 6 = - n - 4n + 4n + 6 = - 5n + 4n + 6 = - n + 6[/tex]

write and equation that represents a vertical stretch by a factor of 3 and a reflection in the x-axis of the graph of g(x)=|x|​

Answers

Answer:

g(x) = -3|x|.

Step-by-step explanation:

Multiplying by 3 stretches the graph vertically by a factor 3 and the negative reflects in the x-axis.

The equation that represents a vertical stretch by a factor of 3 and reflection in x-axis of the graph of function g ( x ) = | x | is given by

f ( x ) = -3 | x |

How does the transformation of a function happen?

The transformation of a function may involve any change.

Usually, these can be shifted horizontally (by transforming inputs) or vertically (by transforming output), stretched (multiplying outputs or inputs),

If the original function is y = f(x), assuming the horizontal axis is the input axis and the vertical is for outputs, then:

Horizontal shift (also called phase shift):

Left shift by c units:  y=f(x+c) (same output, but c units earlier)

Right shift by c units:  y=f(x-c)(same output, but c units late)

Vertical shift:

Up by d units: y = f(x) + d

Down by d units: y = f(x) - d

Stretching:

Vertical stretch by a factor k: y = k × f(x)

Horizontal stretch by a factor k: y = f(x/k)

Given data ,

Let the function be g ( x ) = | x |

Now , let the transformed function be f ( x )

The value of the function f ( x ) is calculated by

Step 1 :

Vertical stretch by a factor of 3

The Vertical stretch by a factor is done by

k: y = k × f(x)

So , multiplying the parent function by 3 , we get

f ( x ) = 3 | x |

Step 2 :

Reflection in the x-axis ,

The value of f ( x ) is multiplied by -1

So ,

f ( x ) = -3 | x |

Therefore , the transformed function f ( x ) = -3 | x |

Hence , The equation that represents a vertical stretch by a factor of 3 and reflection in x-axis of the graph of function g ( x ) = | x | is given by

f ( x ) = -3 | x |

To learn more about transformation of functions click :

https://brainly.com/question/26896273

#SPJ2

A price decreases from $986 to $828.24. What is the percent change?

Answers

Answer:

-16% change

Step-by-step explanation:

The formula for a percent decrease is [tex]\frac{original-new}{original}\cdot100[/tex]. The original value was 986, and the new value is 828.24, so we can substitute inside the equation.

[tex]\frac{986-828.24}{986} \cdot100\\\\\frac{157.76}{986} \cdot100\\\\0.16\cdot100\\\\16[/tex]

So the percent change is -16%.

Hope this helped!

14b + 6 = 6 14b = Subtract 6 from both sides b = Divide both sides by 14

Answers

Answer:

Step-by-step explanation:

((b+2)(b+12)/(b+2)(b+3))*(b+3)

= (b+12)

GUYS I NEED HELP I have no idea what to do and I can’t ask the teacher for help because it’s night already-

Answers

Answer:

x=6

Step-by-step explanation:

127-83=9x-10

44=9x-10

+10.0 +10.0

54=9x

divide by 9 on both sides

x = 6

Simplify: 9y(-3y to the eighth power)

Answers

-27y^4 (^=exponent) so -27y to the fourth power. Hope this helps!

Susan charges $8 per hour walking her neighbor’s dog. She charges $12 per hour babysitting. Part A: Define the variables. Part B: Write an expression to represent the amount Susan earns dog walking and babysitting

Answers

Answer:

the total she earns with "d" hours of dog walking and "b" hours of babysitting is given by:  8 d + 12 b

Step-by-step explanation:

If we use "d" to represent the number of hours that Susan walks the dog, and we define "b" as the number of hours she babysits, then the expression that represents the amount she earns by walking the dog is: $8 times d = 8 d

Similarly, the amount she earns by babysitting is $12 times b = 12 b

Then the total she earns with "d" hours of dog walking and "b" hours of babysitting is:  8 d + 12 b

simplify (7776/343)^2

Answers

Answer:

513.95

Step-by-step explanation:

First you have to divide 7776 by 343. Then you raise the answer to the second power

Owen plots the numbers 4, –6, –8, and –3 on a horizontal number line. Which list shows the numbers in the order in which they would appear from left to right on the number line? –8, –6, –3, 4

Answers

Answer:-8, -6,-3, 4 is the correct answer

Step-by-step explanation:

Answer:

Answer A

Step-by-step explanation:

the sum of two squares of two consecutive natural numbers is 41.Find the numbers​

Answers

AnswEr :

The 2 unknown numbers are 4 and 5 .

Explanation :

Let the numbers be x and x + 1.

From the given information,

[tex]\dashrightarrow\sf \ \ \ x^2 + (x + 1)^2 = 41 \\ \\ \\ [/tex]

[tex]\dashrightarrow\sf \ \ \ 2 {x}^{2} + 2x + 1 = 41 \\ \\ \\ [/tex]

[tex]\dashrightarrow\sf \ \ \ 2 {x}^{2} + 2x + 1 - 41=0 \\ \\ \\ [/tex]

[tex]\dashrightarrow\sf \ \ \ {x}^{2} + x - 20 = 0 \\ \\ \\ [/tex]

[tex]\dashrightarrow\sf \ \ \ (x + 5)(x - 4)=0 \\ \\ \\ [/tex]

[tex]\dashrightarrow\sf \ \ \ { \underline{ \boxed{ \bf{ \red{x = - 5,4}}}}} \ \bigstar \\ \\ [/tex]

But, as we know -5 is not a natural number,

Hence, x = 4 .

So the 2 unknown numbers are :

x = 4 [1st number]

x + 1 = 4 + 1 = 5 [2nd number]

━━━━━━━━━━━━━━━

Solution :

Let the number be x and x + 1.

[tex]\rule{130}1[/tex]

[tex]\underline{ \large \purple{ \mathscr{\dag\:A \bf{ccording} \: to \: \mathscr {Q} \bf{uestion} ....}}}[/tex]

[tex]:\implies\sf x^2 + (x + 1)^2 = 41 \\\\\\:\implies\sf 2x^2 + 2x + 1 - 41 = 0\\\\\\:\implies\sf 2x^2 + 2x + 40 = 0\\\\\\:\implies\sf x^2 + x - 20 = 0\\\\\\:\implies\sf x^2 + x - 20 = 0\\\\\\:\implies\sf x^2 + x - 20 = 0\\\\\\:\implies\sf x^2 + 5x - 4x - 20 = 0\\\\\\:\implies\sf x(x + 5) - 4(x + 5) = 0\\\\\\:\implies\sf (x + 5)(x - 4) = 0\\\\\\:\implies\underline{\boxed{\sf x = -5, 4}}[/tex]

We know that -5 is not a natural number. Hence, x = 4.

[tex]\therefore\:\underline{\textsf{The two consecutive natural number is \textbf{4 and 5}}}.[/tex]

The list price of the item is 80 percent of the original price. The price of the item has been reduced by 80 percent. Write a pair of linear equations using variables of your choice to prove that these two statements are not equivalent. Explain how a calculation for change in percentage (increase or decrease) is different from a calculation that involves multiplying by percentages. Why is the wording of percentage problems so important? Give examples to illustrate your point.

Answers

Answer:

Step-by-step explanation:

Given the expressions :

The list price of the item is 80 percent of the original price. The price of the item has been reduced by 80 percent.

Write a pair of linear equations using variables of your choice to prove that these two statements are not equivalent.

Let the original price = x

Expression 1 : The list price of the item is 80 percent of the original price

List price = 80% of x

List price = 0.8x

Expression 2: The price of the item has been reduced by 80 percent

Price = x - 80% of x

Price = x - 0.8x

Price = 0.2x

Multiply by percentages is different from an Incremental or decrement in percentage. The first expression above signifies a direct multiplication by the stated percentage while the second signifies a decrease in price based on a certain percentage of the original price.

Wording of percentages are so important for clarity in other to understand if the statement signifies a direct application of the percentage prescribed or a change in quantity, amount or size relative to the base unit.

What is the area of a square with the vertices (3, 3), (6, 6), (9,3), and (6,0)?

Answers

Answer:

           A = 18 square units

Step-by-step explanation:

taking A(3, 3), B(6, 6), C(9,3) and D(6,0)

we have:  [tex]y_A=y_C\quad and\quad x_B=x_D[/tex] so the AC and BD are diagonals, that means:

AB = BC = CD = DA = s

[tex]s=\sqrt{(6-3)^2+(6-3)^2}=\sqrt{3^2+3^2}=\sqrt{18}\\\\\\A=s^2=(\sqrt{18})^2=18[/tex]

Taho Earns His Regular Pay Of $11 Per Hour For Up To 40 Hours Of Work Per Week. For Each Hour Over 40 Hours Of Work Per week.For each hour over 40 hours of work per week. Taho earns 1½ times his regular pay. How much does Taho earn in a week in which he works 50 hours?

a. $550
b. $605
c. $625
d. $750
e. $825

Answers

Answer:

$605

Step-by-step explanation:

The correct question is

Taho Earns His Regular Pay Of $11 Per Hour For Up To 40 Hours Of Work Per Week. For each hour over 40 hours of work per week. Taho earns 1½ times his regular pay. How much does Taho earn in a week in which he works 50 hours?

a. $550

b. $605

c. $625

d. $750

e. $825

For the first $40 that Taho works, he earns $11 x 40 = $440

For the extra $10 (since he worked 50 hrs that week)

1½ of $11 per hr = 1.5 x $11 = $16.5

for the 10 days extra = $16.5 x 10 = $165

total pay = $440 + $165 = $605

x2 + 2x -1 = 0 in English words

Answers

Answer:

a number squared plus twice a number minus one equals zero

Step-by-step explanation:

Which table shows a proportional relationship between x and y? A. x y 2 4 3 6 4 9 B. x y 3 4 9 16 15 20 C. x y 4 12 5 15 6 18 D. x y 1 4 2 8 3 15

Answers

Answer:

C.

Step-by-step explanation:

The relationship is proportion if y/x is constant.

So it is C because 12/4 = 15/5 = 18/6 = 3.

x+2/x–2 –x–2/x+2 = 5/6

Answers

(x+2) - (x-2) = 5. (x-2) (x+2) 6. (x+2)² - (x² - 2)² = 5. (x+2) (x-2) 6. (x² + 4x+4) - (x² - 4x + 4) = 5. x² - 4 6. (x² + 4x + 4 - x² + 4x - 4) = 5. x² - 4 6. 8x = 5.

Answer:

(x-10)(5x+2)

Step-by-step explanation:

this is the answer of the question.you can clearly see in the pic of the solution

Which number, when substituted for x, makes the equation 4x+8=16 true?

Answers

X would be 2, 4(2)+8=16.

Answer:

[tex] \boxed{ \bold{ \boxed{ \sf{2}}}}[/tex]

Step-by-step explanation:

[tex] \sf{4x + 8 = 16}[/tex]

Move 8 to right hand side and change its sign

⇒[tex] \sf{4x = 16 - 8}[/tex]

Subtract 8 from 16

⇒[tex] \sf{4x = 8}[/tex]

Divide both sides of the equation by 4

⇒[tex] \sf{ \frac{4x}{4} = \frac{8}{4} }[/tex]

Calculate

⇒[tex] \sf{x = 2}[/tex]

Hope I helped!

Best regards!!

find the sum of the following series
(a) 3+7+11+14+.......(20 terms)
(b)2+6+10+14+.......(15 terms)(c)30+27+24+21+......(40 terms)
(d)5+1+-3+-7+.....(14 terms)
(e)5+7+8+.........+75
(f)4+7+10+.........+91

need explanation
will give the brainliest!

Answers

Answer:

a) 820

b)450

c)  -540

d) -294

e) 1440

f) 1425

Step-by-step explanation:

a) it is an arithmetic progression with ratio=4

   a1=3,

     a2=3+r=3+4=7.....

    a20=a1+19r

so a20=3+19*4=3+76=79

S=(a1+an)*n/2 where n=20

so S=(3+79)*20/2=820

b) a15=a1+14*r=2+14*4=2+56=58

S=(a1+a15)*15/2=(2+58)*15/2=60*15/2=30*15=450

It is the same formula for all  the exercises

S=(a1+an)*n/2 ,     where n is the number of terms

c) a40=30+39*(-3)=30-87=-57

So S=(30-57)*40/2=-540

d) a14=5+13*(-4)=5-52=-47

S=(5-47)*14/2=-42*14/2=-42*7=-294

e) it is 5+7+9+......+75

nr of  terms  = (an-a1) :r+1=(75-5):2+1=36

S=(5+75)*36/2=36*40=1440

f) ratio=7-4=3

the  same formula for n= (91-4):3+1=87:3+1=29+1=30

S=(4+91)*30/2=95*30/2=2850/2=1425

8) За (x-y) - (х-у)​

Answers

Answer:

[tex]3a \times x - y - x - y \\ 3a \times x - x - y - y \\ 3a \times - 2y - \\ - 6ay[/tex]

Answer:

8,3

Step-by-step explanation:

the lunch lady has 6 pounds of lasagna. if she makes 1/2-pounds servings using this lasagna, how many servings can she make?

Answers

Answer:

[tex]\boxed{12}[/tex]

Step-by-step explanation:

[tex]6/\frac{1}{2} =6*2=12[/tex]

A gaming console cost $299.99. Each game that comes with the console is an additional cost of $20.00. Mr. Yao decide to by x number of games Write a variable expression for the number of games Mr. Yao bought

Answers

This question is not correctly written

Complete Question

A gaming console cost $299.99. Each game that comes with the console is an additional cost of $20.00. Mr. Yao decide to by x number of games Write a variable expression for cost of the number of games Mr. Yao bought

Answer:

Variable expression for the cost of the number of games that Mr Yao bought =

$20x

Where x = number of games that he bought.

Step-by-step explanation:

A variable expression can be defined as a mathematical expression where there is at least one (or more) unknown variable(s)that we have to look or solve for.

The unknown variable is always represented by letters of the alphabet, a, b, x, y e.t.c.

A variable expression can also be called an algebraic expression.

From the above question, we are told that:

Cost of a gaming console = $299.99

If you buy a game with the console = Additional $20.00

My Yao bought = x number of games

Variable expression for the cost of the x number of games that Mr Yao bought

$20 × x

= $20x

Where x = number of games that Mr Yao bought.

The discount on a new refrigerator was $250. This was a discount of 18 %
Step 2 of 3: What was the sale price? Follow the problem-solving process and round your answer to the nearest cent, if necessary.

Answers

Answer:

                x = 1388.89

Step-by-step explanation:

x    - the sale price of new refrigerator

18%x = 0.18x   - the discount

0.18x = 250

x = 250÷0.18 = 1388.8888...

x = 1388.89

Name the line and plane shown in the diagram. PLZ ANSWER ASAP, DUE IN 1 HOUR

Answers

Answer:

Line PQ. Not enough Info for the Plano tho.

Step-by-step explanation:

Look at the 2 points, and thats the name of the line.

Expand and combine like terms.
(8 – n^7)(8 +n^7)

Answers

Answer:

Step-by-step explanation:

(a - b)(a + b) = a² - b²

(8 - n⁷)(8 + n⁷) = 8² - (n⁷)² = 64 - n¹⁴      {(aˣ)ⁿ = aˣ*ⁿ }

Or

Use FOIL method

(8 - n⁷)(8 + n⁷) = 8*8 + 8*n⁷ + (-n⁷)*8 + (-n⁷)*n⁷

                       = 64 + 8n⁷ - 8n⁷ - n⁷⁺⁷

                       = 64 - n¹⁴

It says to simplify this, by combinding like terms
8 + 9x + 4 ( 11 – 2x )

Answers

Answer:

52+x

Step-by-step explanation:

[tex]8 + 9x + 4(11 - 2x) \\ = 8 + 9x + 44 - 8x \\ = 8 + 44 + 9x - 8x \\ = 52 + x[/tex]

Foreshadowing is a storytelling device that...
A)Gives hints to reader about a future event.
B)Provides details about a past event.
C)Tells readers that something bad always happens.
D)Creates confusion for the reader.

Answers

Answer:A)Gives hints to reader about a future event.

Step-by-step explanation:

Answer:

A) Gives hints to reader about a future event.

Step-by-step explanation:

Foreshadowing is one of the storytelling device that gives hints to readers about the future events.

Hope this helps ;) ❤❤❤

Does anyone know how to solve this? It’s really starting to stress me out.

PS: You just can solve the lim(x->2) instead of lim(u->0) if u want

Answers

Answer:

π − 12

Step-by-step explanation:

lim(x→2) (sin(πx) + 8 − x³) / (x − 2)

If we substitute x = u + 2:

lim(u→0) (sin(π(u + 2)) + 8 − (u + 2)³) / ((u + 2) − 2)

lim(u→0) (sin(πu + 2π) + 8 − (u + 2)³) / u

Distribute the cube:

lim(u→0) (sin(πu + 2π) + 8 − (u³ + 6u² + 12u + 8)) / u

lim(u→0) (sin(πu + 2π) + 8 − u³ − 6u² − 12u − 8) / u

lim(u→0) (sin(πu + 2π) − u³ − 6u² − 12u) / u

Using angle sum formula:

lim(u→0) (sin(πu) cos(2π) + sin(2π) cos(πu) − u³ − 6u² − 12u) / u

lim(u→0) (sin(πu) − u³ − 6u² − 12u) / u

Divide:

lim(u→0) [ (sin(πu) / u) − u² − 6u − 12 ]

lim(u→0) (sin(πu) / u) + lim(u→0) (-u² − 6u − 12)

lim(u→0) (sin(πu) / u) − 12

Multiply and divide by π.

lim(u→0) (π sin(πu) / (πu)) − 12

π lim(u→0) (sin(πu) / (πu)) − 12

Use special identity, lim(x→0) ((sin x) / x ) = 1.

π (1) − 12

π − 12

there are 15 black marbles and 10 white marbles in a bag. If you pick a marble from the bag without looking, what are your chances of picking a white marble?

Answers

Answer: 40%

Step-by-step explanation:

Answer: 2/5 or 40%

Step-by-step explanation: 15 + 10 = 25 and 10/25 simplifies to 2/5.

Please help me to prove this..​

Answers

Step-by-step explanation:

1 / (sin 10°) − √3 / (cos 10°)

Multiply top and bottom of the first fraction by ½ cos 10°.

½ cos 10° / (½ cos 10° sin 10°) − √3 / (cos 10°)

Multiply top and bottom of the second fraction by ½ sin 10°.

½ cos 10° / (½ cos 10° sin 10°) − ½√3 sin 10° / (½ sin 10° cos 10°)

Combine fractions.

(½ cos 10° − ½√3 sin 10°) / (½ sin 10° cos 10°)

Change ½ to sin 30°, and change ½√3 to cos 30°.

(sin 30° cos 10° − cos 30° sin 10°) / (½ sin 10° cos 10°)

Use angle sum formula.

sin(30° − 10°) / (½ sin 10° cos 10°)

sin 20° / (½ sin 10° cos 10°)

Multiply top and bottom by 4.

4 sin 20° / (2 sin 10° cos 10°)

Use double angle formula.

4 sin 20° / sin 20°

4

We are given the equation 1 / sin(10°) - √3 / cos(10°) = 4, and want to prove that 1 / sin(10°) - √3 / cos(10°) equals 4.

Let's start by combining the expressions '1 / sin(10°)' and '√3 / cos(10°)' in the expression '1 / sin(10°) - √3 / cos(10°).'

1 / sin(10°) - √3 / cos(10°)

= cos(10°) - √3sin(10°) / sin(10°) [tex]*[/tex] cos(10°)

Now let's multiply the numerator and denominator by a common value. In this case it's most suitable to multiply both by 2. We will receive the expression 2(cos(10°) - √3sin(10°)) / 2(sin(10°) [tex]*[/tex] cos(10°)). We can further simplify this expression knowing that 2(sin(10°) [tex]*[/tex] cos(10°)) = 2sin(20°).

2(cos(10°) - √3sin(10°)) / 2sin(20°)

We can now bring the two on the bottom to the numerator, becoming 1 / 2.  Remember that the ' 1 / 2 ' will be distributed now. After the distribution we receive the expression 4( 1 / 2(cos(10°) - √3 / 2sin(10°)) /  2sin(20°). We can now use the trivial functions 1 / 2 = sin(30°), and √3 / 2 = cos(30°).

4(sin(30°)(cos(10°) - cos(30°)(sin(10°) ) / sin(20°))

= 4((sin(30 - 10°)) / sin(20°) = 4

Other Questions
"Would you prefer to work the morning shift, the afternoon shift, or the evening shift?" is an example of why did the Vietnam war happen? (02.01)Line segment EF has a length of 5 units. It is translated 5 units to the right on a coordinate plane to obtain line segment E'F'. What is the length of E'F'? 5 units 6 units 10 units 25 unitsThe line segments are translated 2 units to the left to form J'K' and M'N'. Which statement describes J'K' and M'N'? Line segments J'K' and M'N' do not intersect and are closer together than JK and MN. Line segments J'K' and M'N' intersect at (2, 0) and are two times farther apart than JK and MN. Line segments J'K' and M'N' intersect at (0, 2) and are two times closer together than JK and MN. Line segments J'K' and M'N' do not intersect and are the same distance apart as JK and MN. Which length of time is a decade?O 1950 to 1959O 1600 to 1699O 1000 to 1999O 1200 to 1399 Write an expression in terms of x that represents the distance between (2,10) and (x,10) for x>2. A budget for short-term goals involving recurring items is called a/an:______.a. operating budgetb. comprehensive budget. c. capital budget. d. a. and b. e. a, b, and c. 6. Combine like terms. What is the simplified form of the expression?6a + 8 + 2a 6= State the name of electromagnetic wave other than visible light ? Write a unit rate that compares the quantities described.180 people on 3 planes. Any ideas for a fictional books characters setting etc. who is the prime minister of Pakistan If a plane travels 990 kilometers in two hours, what is its speed in kilometers per hour? Please do in separate answers... Why was the Federalist Papers #10 written? Why was the Federalist Papers #51 written? Why was President George Washington's Farewell Address written? Rachel deposited $5,960.32 into a savings account with an interest rate of 4.2% compounded twice a year. About how long will it take for the account to be worth $9,000? (3 points) a 21 years, 1 month b 18 years, 0 months c 19 years, 10 months d 9 years, 11 months ?????? help pls lolll Cliques can sometimes exclude others from the group. True False Fill in the black with the spanish word that best completes this sentence a man who has no hair is?A. peloB. calvo C. seguroD. negro Simplify using order of operations: 10/2+3+6+3/3 If the cost to buy a part is less than the direct material, direct labor, and incremental overhead cost of making the part, the company should buy the part.a. Trueb. False The students in the diagram are communicating with the can and string. Which term best describes the sound wave that travels along the string