<img src="https://tex.z-dn.net/?f=Factor%3A%20x%5E2-9" id="TexFormula1" title="Factor: x^2-9" alt="Factor: x^2-9" align="absmidd

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Arada [10]

3 years ago

le" class="latex-formula">

Mathematics

1 answer:

Bezzdna [24]3 years ago

7 0

Answer:

x²-9=x²-3²=(x+3)(x-3)

Step-by-step explanation:

use formula

a²-b²=(a+b)(a-b)

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What is the volume of this pyramid? 945 cm³ 1260 cm³ 1890 cm³ 2520 cm³ A pyramid with a right triangular base. The right triangu

notsponge [240]

Answer:

The volume of the pyramid is $1,260\ cm^{3}$

Step-by-step explanation:

we know that

The volume of the triangular pyramid is equal to

$V=\frac{1}{3}BH$

where

B is the area of the triangular base

H is the height of the pyramid

step 1

Find the area of the base B

$B=\frac{1}{2}bh$

we have

$b=14\ cm$

$h=18\ cm$

substitute

$B=\frac{1}{2}(14)(18)=126\ cm^{2}$

step 2

Find the volume

we have

$B=126\ cm^{2}$

$H=30\ cm$

substitute

$V=\frac{1}{3}BH$

$V=\frac{1}{3}(126)(30)=1,260\ cm^{3}$

5 0

3 years ago

Read 2 more answers

After breaking your penny bank, you notice that you have $4.87 in quarters ($0.25), dimes ($0.10), nickels ($0.05), and pennies

ira [324]

Answer: Option 'c' is correct.

Step-by-step explanation:

Let the number of dimes be 'x'.

Let the number of nickels be ' $\dfrac{3}{2}x$ '.

Let the number of pennies be $\dfrac{3}{2}\times 2x=3x$

Let the number of quarters be '3x-34'.

As we know that

1 quarter = $0.25

1 dime = $0.10

1 nickel = $0.05

1 penny = $0.01

According to question, we get that

$0.10x+0.05\times \dfrac{3x}{2}+0.01\times 3x+0.25(3x-34)=4.87\\\\0.10x+0.075x+0.03x+0.75x-8.5=4.87\\\\\\0.955x=4.87+8.5\\\\0.955x=13.37\\\\x=\dfrac{13.37}{0.955}\\\\x=14$

So, the number of pennies is given by

$3x=3\times 14=42$

Hence, Option 'c' is correct.

3 0

3 years ago

Triangle ABC is being dilated with the center of dilation at the origin. The image of C, point C' has coordinates of (7.2, 3.6).

MAXImum [283]

General Idea:

When we are given a point P(x, y) centered at origin with a scale factor of k, then the dilated point will be given by P' (kx, ky)

Applying the concept:

In the diagram given, the coordinate of C is (6, 3). Triangle ABC is being dilated with the center of dilation at the origin. The image of C, point C' has coordinates of (7.2, 3.6).

If C (x, y) centered at origin with a scale factor of k, then the dilated point will be given by C' (kx, ky)

We know $x = 6$ & $kx = 7.2$

Substituting 6 for x in the equation $kx = 7.2$ , we get $6k = 7.2$ .

Dividing 6 on both sides $\frac{6k}{6}=\frac{7.2}{6}$

Simplifying fractions on both sides $k=1.2$

Point A from the diagram is (-3, 3)

x-coordinate of A' = $kx=1.2 * -3 = -3.6$

y-coordinate of A' = $ky =1.2*3=3.6$

Point A' is given by (-3.6, 3.6)

Conclusion:

<u>Scale factor of dilation is 1.2</u>

<u>The coordinates of point A' is (-3.6, 3.6)</u>

6 0

4 years ago

Read 2 more answers

danielle did not complete 15 of her 200 assignments last year. Kim said that is 0.075 of her assignments and Kelly said it is 0.

Alona [7]

Answer:

Kim

is correct

Step-by-step explanation:

Here, we want to know who is correct between Kim and Danielle

From the question, what is not completed is 15 out of 200

To find what is not completed, we divide 15 by 200

Thus, we have;

15/200 = 0.075

This mean Kim is correct

3 0

3 years ago

A chicken salad recipe calls for 1 8

NARA [144]

Answer: $1.0625\ pounds$ or $\frac{17}{16}\ pounds$

Step-by-step explanation:

The complete exercise is: "A chicken salad recipe calls for $\frac{1}{8}$ pound of chicken per serving . How many pounds of chicken are needed to make $8\frac{1}{2}$ serving".

You can convert the Mixed number to a Decimal number. Divide the numerator 1 by the denominator 2 and then add the quotient to the Whole number. Then, you get:

$8+0.5=8.5$