A teacher interested in determining the effect of a new computer program on learning to read conducted a study. One hundred students were randomly assigned to one of tu
groups. The first group used the computer program while the second group did not. Both groups were tested to determine how much their reading levels improved. The results for the two groups were compared. What kind of study is this?

Answer:

x^2+3x-4

Step-by-step explanation:

(x-1)(x+4)

x^2+4x-x-4

x^2+3x-4

Hope this helps ;) ❤❤❤

Answer:

y = x² + 3x -4

Step-by-step explanation:

we can use the FOIL formula

(x-1) (x+4)

x² + 4x - x -4

x² + 3x -4

therefore, the standard form would be y = x² + 3x -4

Answer:

291 cm³

Does the answer help you?

Answer:

1.72

Step-by-step explanation:

AB tangent at D, AD = OD = 4

so triangle OAD is right angle with side of 4 and 4.

area of OAD = 1/2 * 4 * 4 = 8

Angle AOD = DAO = 45 deg.

so circular sector OCD area = area of circle O * 45/360

= pi * 4 * 4 * 45/360

= 2pi

Shade area ACD = trigangle OAD - circular sector OCD

= 8 - 2pi

= 1.72

Answer:

the function is a y-intercept

Step-by-step explanation:

y=mx+b is the slope intercept formula, m being the slope and b being the y-intercept, meaning y=b, so b=-9/4.

Because it says y=-9/4, we can assume that m, or the slope equals 0.

so when you plug it in, you get

y=0x-9/4

y=-9/4

Answer:t below the pool’s surface. What is the total length of Tommy’s dive?

7 feet

Step-by-step explanation:

Answer:

These two triangles are similar triangles. This means that their side lengths are proportional to each other.

Thus, making line segment EC equal to "x", and BC equal to "y" we can write:

8/y = 28/(10+y)

The next step is to get rid of the fractions, which can be done by cross multiplying.

So we have:

8(10+y) = 28(y)

After distribution and some simplification, you should get the value of y.

80+8y = 28y

80 = 20y

80/20 = 20y/20

4 = y

y = 4

Knowing that y = BC, and y = 4, it is clear that BC = 4.

Since BC = 4, one can use the Pythagorean Theorem to solve for segment EC.

Pythagorean Theorem: a^2 + b^2 = c^2, where a and b are the side lengths of a right triangle, and c is the hypotenuse (in other words the longest side)

In our case, a and  b are 8 and 4 (the order doesn't really matter here).

So we have: 8^2 + 4^2 = c^2

64 + 16 = c^2

80 = c^2

c = sqrt 80

c  = 4 sqrt 5

And we arrive at the answer- EC = 4 sqrt 5, making B the correct choice.

Hope this helps!

Answer:

To fine the missing value JUST transpose

___ -(-5) = -7       {- * - = +}

___ +5 = -7

___ = -7-5

___= -12

so the missing place is -12

Answer:

-12

Step-by-step explanation:

Answer:

Question 1: $100

Question 2: Myself

Question 3: Yes, because you get to buy things you might have been wanting, or saving up for.

Question 4: Yes, because its an easier way of shopping, and gets sent straight to your home.

Step-by-step explanation:

Hope this helps.

Answer:

31

Step-by-step explanation:

Given

x² + 5x - 3 = 0

with a = 1, b = 5, c= - 3 , then

sum of roots x₁ + x₂ = - [tex]\frac{b}{a}[/tex] = - [tex]\frac{5}{1}[/tex] = - 5

product of roots = [tex]\frac{c}{a}[/tex] = [tex]\frac{-3}{1}[/tex] = - 3

Now

(x₁ + x₂)² = x₁² + 2x₁x₂ + x₂² , that is

(- 5)² = x₁² + 2(- 3) + x₂²

25 = x₁² - 6 + x₂² ( add 6 to both sides ), then

x₁² + x₂² = 31

Answer:

16x^2 + 24x + 9  

Step-by-step explanation:

perfect square trinomial is of the form

a^2 + 2 * a * b + b^2

9x^2 + 9x + 1   = (3x)^2 + 3*3x*1 + 1^2  not a perfect square trinomial

36b^2 − 24b + 8  = ( 6b)^2  -2 * 6b *2 + ( 2 sqrt(2)) ^2  not a perfect square trinomial

16x^2 + 24x + 9  = ( 4x) ^2 + 2 * ( 4x) * 3 + 3^2 = perfect square trinomial

4a^2 − 10a + 25 = ( 2a) ^2 -  1 * 2a *5 + 5^2   not a perfect square trinomial

Answer:

The third answer listed:

[tex]16x^2+24x+9[/tex]

Step-by-step explanation:

The trinomial:  

[tex]16x^2+24x+9[/tex]

can be factored out as follows:

[tex]16x^2+24x+9\\(4x)^2+24x+3^2\\(4x)^2+12x+12x+3^2\\4x(4x+3)+3(4x+3)\\(4x+3)\,(4x+3)\\(4x+3)^2[/tex]

which as can be seen,is the perfect square of a binomial, so this trinomial is what is called a perfect square trinomial.

Answer:

Step-by-step explanation:

The expression

- 3x³

To find the value of the expression when

x = 4 substitute the value of x that's 4 into the expression

We have

- 3(4)³

= - 3( 64)

The final answer is

Hope this helps you

Answer:

{x | x is a real number}

Step-by-step explanation:

f(x) = 5x – 7

There are no restrictions on the value that x can take

The domain is all real numbers

Answer:

In the given expression, that is, f (x) = 5x - 7, we can say:

x satisfies all the real values starting from -∞ to ∞.

domain of 5x-7

Interval notation for f (x):

(- ∞ , ∞)

So, the domain will be all real numbers, as the function is a straight line, with no discontinuities, thus undefined at no value of x.

Answer:

c

Step-by-step explanation:

x³ - y³ ← is a difference of cubes and factors as

x³ - y³ = (x - y)(x² + xy + y²)

Given

[tex]\frac{x}{y}[/tex] + [tex]\frac{y}{x}[/tex] = - 1

Multiply through by xy to clear the fractions

x² + y² = - xy ← substitute into second factor of expansion

x³ - y³ = (x - y)(- xy + xy) = (x - y) × 0 = 0 → c

Answer:

The answer is C. 0

Step-by-step explanation:

since

[tex] \frac{x}{y} + \frac{y}{x } = - 1[/tex]

we multiply both sides by xy to cancel their denominators and multiply -1 by xy

so we have

[tex]xy( \frac{x}{y}) + xy( \frac{x}{y} ) = xy \times - 1[/tex]

we get our answer as

[tex] {x}^{2} + {y}^{2} = - xy[/tex]

we were given the difference of cubes that is

[tex] {x}^{3} - {y}^{3} [/tex]

which is =

[tex](x - y)( {x}^{2} + xy + {y}^{2} )[/tex]

so since,

[tex] {x}^{2} + {y}^{2} = - xy[/tex]

we substitute,

[tex](x - y)( - xy + xy) = (x - y)(0) = 0[/tex]

Answer:

d = 19/5 or, 4.75 in decimal form

Step-by-step explanation:

Answer:

[tex]\frac{-17}{15}[/tex]

Step-by-step explanation:

When solving this problem you must follow PEMDAS, so parentheses should go first. To solve 1/10 - 2/3, first, find the common denominator. In this case, that is 30. Then, subtract, [tex]\frac{3}{30} - \frac{20}{30}[/tex]. This equals -17/30. Finally, divide by 0.5. To do this remember that dividing by half is the same as multiplying by 2. Doing [tex]\frac{-17}{30} *2[/tex] equals [tex]\frac{-17}{15}[/tex].

Answer:

[tex] { x^2+3x-4} [/tex]

Step-by-step explanation:

Factor top and bottom.

The numerator is a difference of two squares, and the denominator is a quadratic.

[tex] \frac{ {9x}^{2} - {(x}^{2} - 4)^{2} }{4 + 3x - {x}^{2} } [/tex]

= [tex]\frac{ (3x+x^2-4)(3x-x^2+4) }{(1+x)(4-x)}[/tex]

= [tex] \frac{ (x-1)(x+4) (1+x)(4-x) }{(1+x)(4-x)} [/tex]

If x does not equal -1 and does not equal 4, we can cancel the common factors in italics to give

= [tex] { (x-1)(x+4)} [/tex]

= [tex] { x^2+3x-4} [/tex]

Answer:

The answer is

Step-by-step explanation:

[tex] \frac{9 {x}^{2} - ( { {x}^{2} - 4})^{2} }{4 + 3x - {x}^{2} } [/tex]

To solve the expression first factorize both the numerator and the denominator

For the numerator

9x² - ( x² - 4)²

Expand the terms in the bracket using the formula

( a - b)² = a² - 2ab + b²

(x² - 4) = x⁴ - 8x² + 16

So we have

9x² - (x⁴ - 8x² + 16)

9x² - x⁴ + 8x² - 16

- x⁴ + 17x² - 16

Factorize

that's

(x² - 16)(-x² + 1)

Using the formula

a² - b² = ( a + b)(a - b)

We have

(x² - 16)(-x² + 1) = (x + 4)(x - 4)( 1 - x)(1 + x)

For the denominator

- x² + 3x + 4

Write 3x as a difference

- x² + 4x - x + 4

Factorize

That's

- ( x - 4)(x + 1)

So we now have

[tex] \frac{(x + 4)(x - 4)( 1 - x)(1 + x)}{ - (x - 4)(x + 1)} [/tex]

Simplify

[tex] \frac{ - (x + 4)(1 - x)(1 + x)}{x + 1} [/tex]

Reduce the expression by x + 1

That's

-( x + 4)( 1 - x)

Multiply the terms

We have the final answer as

Hope this helps you

Answer:

4

Step-by-step explanation:

i dont really know how to explain i used an algebra calculator

Answer:

...

Answer:

k=10BY DPING PROCESS IT BECOME

Answer:

The correct answer is the final option, 2.

Step-by-step explanation:

[(16+4) - 10] - 8

Our first step in this problem, according to the order of operations, is to simplify what is inside the parentheses.  Since there are multiple sets of parentheses, we must simplify the innermost group first.  If we add 16 and 4, we get:

[20 - 10] - 8

Next, we must perform the subtraction inside the parentheses.  This gives us:

10 - 8

Now, we can perform the final operation.  

10 - 8 = 2

Therefore, the correct answer is 2.

Hope this helps!

Answer:

B

Step-by-step explanation:

it is defined for all values so D=R

also we can get any value

so Range =R

Answer:

B

Step-by-step explanation:

because that's odd power function it can take both, negative and positive values

Answer:

75%=x-125

90%=x+250

subtract the second from the first

15%=375

100%=?

100%×375/15

100%=2500marked price is 2500

2500+250=2750

90%=2750

100%=?

cost price=3055.56

Answer:

28 : 37

Step-by-step explanation:

Find how many male teachers there are by subtracting 9 from 37:

37 - 9

= 28

Create a ratio with this to the total number of teachers:

28 : 37

So, the ratio of the number of male teachers to the total number of teachers is  28 : 37.

Answer:

3 ft per minute

Step-by-step explanation:

Take the distance and divide by the time

3/4 ft ÷ 1/4 minute

Copy dot flip

3/4 * 4/1

Rewriting

3/1 * 4/4

3/1 *1

3 ft per minute

( − 2 ) ( 3+ 2 2 − − 2 )

Hope this helps, have a great day!

Answer:4 ans x is -32/10

7 ans b  is 6

10 ans x is 25/7

13 ans x is 9/2

Step-by-step explanation:

please mark this answer as brainlist

Answer:

  GH = 16; CH = 12

Step-by-step explanation:

First of all, you need to understand the meaning of "perpendicular bisector." It means that GH is divided into two equal parts by line AC, and that AC makes a right angle to GH.

The right angle is marked.

(a) The length of one of the halves of GH is marked as being 8 units long, so the other half will also be 8 units long. Of course, the length of GH is the sum of its two halves:

  GH = GB +BH = 8 + 8

  GH = 16

__

(b) Triangles CBG and CBH share side CB, so have that length in common. They have equal lengths BG and BH because BC bisects GH. They have a right-angle at B in common, so can be considered congruent by SAS, the fact that two congruent sides have a congruent angle between them.

Since triangles CBG and CBH are congruent, their corresponding sides CG and CH are also congruent. Side CG is marked 12 units long, so CH will be 12 units long, also.

  CH = 12

You could shortcut all of the congruent triangle logic by recognizing that an altitude (CB) is a perpendicular bisector of the base (GH) if and only if the triangle is isosceles. The sides of an isosceles triangle are always congruent, so CG = CH = 12.

__

In part (c), you're supposed to choose possible theorems for demonstrating the congruence of the triangles we described above.

Answer:

Step-by-step explanation:

2(75)=150 that's the amount due in total for two months so

400-150= 250 they will owe $250 after two months payment

The length of the rectangular delivery box must be equal to 4 inches.

Let the length of the box be L.

Let the width of the box be W.

Let the height of the box be H.

Given the following data:

Translating the word problem into an algebraic expression;

[tex]W = 3 + L[/tex]  ......equation 1

[tex]H = 4 + L[/tex]  ......equation 2.

Mathematically, the volume of a rectangular solid is given by the formula;

[tex]Volume = length * width * height[/tex]  .....equation 3.

Substituting the values into equation, we have;

[tex]224 = L * (3 + L) * (4 + L)\\\\224 = (3L + L^{2})* (4 + L)\\\\224 = 12L + 3L^{2} + 4L^{2} + L^{3} \\\\224 = 12L + 7L^{2} + L^{3}[/tex]

Rearranging the polynomial, we have;

[tex]L^{3} + 7L^{2} + 12L - 224 = 0[/tex]

We would apply the remainder theorem to solve the polynomial.

According to the remainder theorem, if a polynomial P(x) is divided by (x - r) and there is a remainder R; then P(r) = R.

When x = 3

[tex](x - 3) = 0\\x = 3[/tex]

[tex]P(3) = 3^{3} + 7(3^{2}) + 12(3) - 224\\\\P(3) = 27 + 7(9) + 36 - 224\\\\P(3) = 27 + 63 + 36 - 224 = -98 \neq 0[/tex]

We would try with 4;

[tex]P(4) = 4^{3} + 7(4^{2}) + 12(4) - 224\\\\P(4) = 64 + 7(16) + 48 - 224\\\\P(4) = 64 + 112 + 48 - 224\\\\P(4) = 224 - 224 = 0[/tex]

Therefore, 4 is one of its roots.

Hence, the length of the rectangular delivery box must be equal to 4 inches.

Find more information on polynomial here: https://brainly.com/question/10689855