Can someone please explain the answers?

Answer:

10 incorrect answers

Step-by-step explanation:

From the information given, you can say that 5 marks for the number of correct answers minus two marks for the number of incorrect answers is equal to 30 that is the score that Radhika got:

(5*10)-2x= 30, where x is the number of incorrect answers.

Now, you can solve for x:

50-2x=30

50-30=2x

20=2x

x=20/2

x=10

According to this, the answer is that they attempted 10 incorrect answers.

=========================================================

Explanation:

We can prove this by contradiction.

Let's say

and

A+B = C

We'll show that a contradiction happens based on this.

If A is rational, then A = p/q where p,q are two integers. The q cannot be zero.

If C is rational, then C = r/s for some other integers. We can't have s be zero.

Note the following

A+B = C

B = C - A

B = r/s - p/q

B = qr/qs - ps/qs

B = (qr - ps)/qs

B = (some integer)/(some other integer)

This shows B is rational. But this is where the contradiction happens: We stated earlier that B was irrational. A number cannot be both rational and irrational at the same time. The very definition "irrational" literally means "not rational".

In short, I've shown that if A+B = C such that A,C are rational, then B must be rational as well.

The template is

rational + rational = rational

Therefore, we've shown that if A is rational and B is irrational, then C cannot possibly be rational. C is irrational.

Another template is

rational + irrational = irrational

Answer:

48 girls tried out for the team.

Step-by-step explanation:

The phrase "2 out of every 9" can be written as the fraction 2/9. To find our answer, all we have to do is 2/9 * 216 = 48 girls.

Answer:

1260 ounce of the fluid.

Step-by-step explanation:

Dimension of hallway = 90 feet × 7 feet

Area of the hallway = 90 × 7

                                  = 630 square feet

Given that 1/2 (0.5) of a fluid ounce is required per square foot, the amount of cleaning situation to clean the hallway can be determined as;

                 =  [tex]\frac{area of hallway}{cleaning situation per foot}[/tex]

                 = [tex]\frac{630}{0.5}[/tex]

                 = 1260 ounce

The amount of cleaning situation required to clean the hallway is 1260 ounce of the fluid.

Answer:

a: x=90 b: x=45 y=45 c: y=68 x=68

Answer:

f(x) = 5 * ( 8/5) ^x

Step-by-step explanation:

f(x) = a b^x

Let x = 0

5 = a * b^0

5 = a*1

a = 5

Let x = 1

8 = 5 * b^1

Divide each side by 5

8/5 = b

f(x) = 5 * ( 8/5) ^x

Fred's age is 13 years

Let

Fred's age = x

Jack's age = 2x + 4

After 8 years:

= 2x + 12

Sum of their ages = Fred's age + Jack's age

59 = (x + 8) + (2x + 12)

59 = x + 8 + 2x + 12

59 = 3x + 20

59 - 20 = 3x

39 = 3x

x = 39/3

x = 13 years

Therefore, Fred's age = 13 years

https://brainly.com/question/24371832

1. (a) 0 = x² + 4x - 12 (Switch Sides)

x² + 4x - 12 = 0 (Factor Expression)

(x - 2)(x + 6) = 0 (Apply the Zero Factor Principle)

x = 2, and x = - 6

x - intercept : (2, 0) and ( - 6, 0)

(b) y = (0)² + 4(0) - 12 (Simplify)

y = 0 + 4 * 0 - 12 = 0 + 0 - 12 = - 12

y - intercept : (0, - 12)

(c) Our vertex belongs to an upward facing parabola, and hence it will be a minimum, of ( - 2, - 16).

2. Seth's solution is not accurate. He did the calculations accurately, and ended up with x = 3 and x = - 2. However he forgot to substitute those values back into the equations y = x² + 3x - 5 and y = 4x + 1, solving for the y values. Instead of being ( - 2, 0) and (3, 0) it should have been (3, 13), ( - 2, - 7)...

y = (3)² + 3(3) - 5 = 9 + 9 - 5 = 18 - 5 = 13,

y = 4( - 2) + 1 = - 8 + 1 = - 7

Hence we get the solutions (3, 13) and ( - 2, - 7).

Answer:

3

Step-by-step explanation:

Add up the exponents of the variables

5xyz​ = 1+1+1 = 3

The degree is 3

Answer:

First, just to recap, a  degree of a polynomial is the highest power that it is raised to.

For example, 2x^4 + 3x - 7, is a 4th degree polynomial.

5xyz is a has a degree of 3, since the highest power that it is raised to is to the power of 1, and has 3 terms.

Let me know if this helps!

Answer: 14.855

Step-by-step explanation: 27.425 - 12.570 = 14.855

Answer:

x=42

Step-by-step explanation:

Answer:

Hey there!

The first equation has no solutions, as it is parallel lines.

The second equation has infinitely many solutions, as it is basically the same line, and the two lines intersect at infinite points.

The third equation is just one solution.

Let me know if this helps :)

Answer:

1 - No solution

2 - Infinitely many solutions

3 - One solution

Step-by-step explanation:

Hey there!

Well to find if there is no solution, one solution, or infinitely many we need to look at the slope and y intercept.

1) - No solution

This is no solution because both slopes are the same meaning they are parallel meaning they have no solution.

2) - Infinitely many solutions

We need to convert into slope-intercept.

y = -x + 4

y = -x + 4

Since both slopes and y-intercepts are the same they overlap meaning they have infinite solutions.

3) - One solution

Slope-intercept,

y = -3x + 11

y = -1/3x + 1/3

Because both slopes are y-intercepts are different they have only one solution.

Hope this helps :)

Answer:

Each shade has a 22.5 degree angle from the middle

Each unshaded has a 67.5 degree angle from the middle.

Step-by-step explanation:

You can solve this by making each unshaded part equal to x and each shaded part equal 1/3x it is a circle so it has to equal 360 so you end up with:

x + 1/3x + x + 1/3x + x + 1/3x + x + 1/3x = 360

Combine Like terms:

16/3x = 360

Multiply both sides by the opposite:

(3/16) (16/3x) = (360) (3/16)

x=135/2 or x=67.5

Then you can plug 67.5 in for x:

1/3x ---> 1/3(67.5) = 22.5

Answer:

10

Step-by-step explanation:

This is a combinations problem, involving factorials.

5!/3!*2!=5*4/2=20/2=10

The different sum of the 4 coins from the list of 5 coins is an illustration of combination or selection. There are 5 different possible sums.

Given

[tex]n = 5[/tex] --- number of coins

[tex]r = 4[/tex] --- coins to be selected to calculate sum

For the sum of the coin value to be calculated, the 4 coins must be selected. This means combination.

So, we make use of:

[tex]^nC_r = \frac{n!}{(n - r)!r!}[/tex]

This gives

[tex]^5C_4 = \frac{5!}{(5 - 4)!4!}[/tex]

[tex]^5C_4 = \frac{5!}{1!4!}[/tex]

Expand

[tex]^5C_4 = \frac{5*4!}{1*4!}[/tex]

[tex]^5C_4 = \frac{5}{1}[/tex]

[tex]^5C_4 = 5[/tex]

Hence, there are 5 different possible sums.

Read more about combinations at:

https://brainly.com/question/15401733

Answer:

True

Step-by-step explanation:

For one-to-one function, we have for all x₁ and x₂, where x₁ ≠ x₂, then, f(x₁) ≠ f(x₂)

Which gives;

f

Where f(x₁) = y₁, the result of the inverse of the f⁻¹(y₁) = x₁

By definition the inverse of a one-to-one function, f⁻¹ is a distinctive function whose domain is given by f⁻¹(f⁻¹(x)) = x for the values of x in f

Therefore, for one-to-one functions, f⁻¹(f⁻¹(x₁)) = x₁

Where f⁻¹(x₁) = y₁, is the inverse or reverse of a function f(x₁), therefore, we have;

f⁻¹(y₁) = x₁

Which proves the statement that y = f(x) then x= f⁻¹(y).

Answer:

-3 and infinity

Step-by-step explanation:

—3/2 X + Y = —7/2

This is the standard form

Refer the attached image for the answer

HOPE SO IT HELPS YOU

Answer:

0.86, 8.14

Step-by-step explanation:

Answer:

9.

Step-by-step explanation:

45 / [8(5 - 4) - 3]

= 45 / (8 * 1 - 3)

= 45 / (8 - 3)

= 45 / 5

= 9.

Hope this helps!

Answer:

96 km/h

Step-by-step explanation:

Speed of car = 87 km/h

Time = 20 minutes = [tex]\frac{20}{60} = \frac{1}{3}\ hrs[/tex]

Distance traveled by bus = 3 km more than that of traveled by car

To find

Average speed of bus = ?

Solution:

Formula for distance traveled is given as:

[tex]Distance = Speed \times Time[/tex]

So, distance traveled by car in 20 minutes = 87 [tex]\times \frac{1}3[/tex] = 29 km

As per given statement, distance traveled by bus = 29 + 3 = 32 km

Time taken = [tex]\frac{1}{3}\ hrs[/tex]

Using the formula:

[tex]Speed = \dfrac{Distance}{Time}[/tex]

Speed of the bus =

[tex]\frac{32}{\frac{1}3} = \bold{96\ km/h}[/tex]

Answer:

$0.56, or 56¢.

Step-by-step explanation:

According to the picture, there are two dimes, two nickels, a penny, and a quarter.

A penny is worth $0.01.

A nickel is worth $0.05.

A dime is worth $0.10.

A quarter is worth $0.25.

2(0.1) + 2(0.05) + (0.01) + (0.25) = 0.2 + 0.1 + 0.01 + 0.25 = 0.3 + 0.26 = 0.56.

So, Vivian is using $0.56, or 56¢, to buy a toy. That's a cheap one!

Hope this helps!

Answer

1 + 5 ÷ 5

This would equal 2, using BIDMAS.

Answer:

15 / 1

hope that helps uh...☺

Answer:

Step-by-step explanation:

We can find the answer by multiplying the number of donuts, 12, by the price he sells each donut for, $0.75, and subtracting that answer from the price he paid.

By making the equation 12 × 0.75 = $9 - $3.99 we can find out that he makes $5.01 in profit.

Answer:

3/4

Step-by-step explanation:

4/4-1/4=3/4

i hoped this helped :)

Answer:

3/4

Step-by-step explanation:

The angle is negative to indicate a clockwise rotation.

======================================================

Explanation:

Z = -3 - 8i is in the form z = a+bi with a = -3 and b = -8

In the complex plane the point (a,b) represents the location of z = a+bi

Define three points with the locations

P = (a,b) = (-3,8)

Q = (0,0)

R = (10,0)

The angle PQR is the angle theta we're looking for. This is the angle formed between the positive x axis and the terminal point (a,b)

Use the arctan function to find theta

theta = arctan(b/a)

theta = arctan( (-8)/(-3) )

theta = 69.4439547804166

theta = 69.4 degrees approximately

Note how this theta value is in quadrant Q1, but (a,b) = (-3, -8) is in Q3

So we need to add 180 degrees to adjust this error.

69.4+180 = 249.4

and we're now in the proper quadrant. We would stop here if your teacher did not put the restriction that theta must be between -180 and 180.

However, this restriction is in place so we need to find the difference of 360 and 249.4 to get 360-249.4 = 110.6

-----------

The angle 249.4 degrees is coterminal to -110.6 degrees. They both point in the same direction.

angle 249.4 degrees is found by starting pointing directly east and rotating 249.4 degrees counterclockwise

angle -110.6 degrees is found by starting directly east and rotating 110.6 degrees clockwise.

Check out the diagram below. I used GeoGebra to make the diagram.

Answer:

29

Step-by-step explanation:

conjugate of a+ib=a-ib

conjugate of 2-5i=2+5i

(2+5i)(2-5i)=2²-(5i)²=4-25i²=4-25(-1)=4+25=29

Answer:

29

i had the same question and 29 was the right answer

Answer:

x = 3

y = -1

Step-by-step explanation:

Based on the fact that our have two variables and two equations, I'm going to assume you are trying to find the values of x and y.

For these two equations, let's first find the value of x using the equation elimination method.

We're going to eliminate the y variable by multiplying the first equation by 2 and then adding that new equation to the second equation.

7x - y = 22 ==> 14x - 2y = 44

4x + 2y + (14x - 2y) = 10 + (44)

18x + 0y = 54

x = 3

Now we plug the value of x back into one of the equations to find the value of y.

7x - y = 22

7(3) - y = 22

-y = 22 - 21

y = -1

So our values are as follows:

x = 3

y = -1

Cheers.