Answer:
ratio of boys to girls= 4:7
number of girls=21
now,
![\frac{boys}{girls} \times \frac{no.of \: boys}{no.of \: girs}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bboys%7D%7Bgirls%7D%20%20%5Ctimes%20%5Cfrac%7Bno.of%20%20%5C%3A%20boys%7D%7Bno.of%20%5C%3A%20girs%7D%20)
![\frac{4}{7} \times \frac{boys}{21}](https://tex.z-dn.net/?f=%20%5Cfrac%7B4%7D%7B7%7D%20%20%5Ctimes%20%20%5Cfrac%7Bboys%7D%7B21%7D%20)
![4 \times 21 = 7boys\: \\ \: ({cross multiplication})](https://tex.z-dn.net/?f=4%20%5Ctimes%2021%20%3D%207boys%5C%3A%20%5C%5C%20%20%20%5C%3A%20%20%28%7Bcross%20multiplication%7D%29)
![84 = 7boys](https://tex.z-dn.net/?f=84%20%20%3D%207boys)
![\frac{84}{7 \: } = boys \: \: \: (dividing \: 84 \: by \: 7)](https://tex.z-dn.net/?f=%20%5Cfrac%7B84%7D%7B7%20%5C%3A%20%7D%20%20%3D%20boys%20%5C%3A%20%20%5C%3A%20%20%5C%3A%20%28dividing%20%5C%3A%2084%20%5C%3A%20by%20%5C%3A%207%29)
![12 = boys](https://tex.z-dn.net/?f=12%20%3D%20boys)
![no.of \: boys = 12](https://tex.z-dn.net/?f=no.of%20%5C%3A%20boys%20%3D%2012)
Answer:
y=−1/6x−6
Step-by-step explanation:
Answer:
calculator
Step-by-step explanation:
calculator
The expressions are simplified to 2x and ![\frac{2}{(x+ 1)(x - 1)}](https://tex.z-dn.net/?f=%5Cfrac%7B2%7D%7B%28x%2B%201%29%28x%20-%201%29%7D)
<h3>How to simply the expressions</h3>
1.
Given the expression;
![\frac{8x^2 - 4x}{4x - 2}](https://tex.z-dn.net/?f=%5Cfrac%7B8x%5E2%20-%204x%7D%7B4x%20-%202%7D)
Let's factorize the numerator;
![\frac{2x( 4x - 2)}{4x - 2}](https://tex.z-dn.net/?f=%5Cfrac%7B2x%28%204x%20-%202%29%7D%7B4x%20-%202%7D)
Factor the common terms, we have;
2x
2. ![\frac{1}{x-1} - \frac{2}{x} + \frac{1}{x + 1}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bx-1%7D%20-%20%5Cfrac%7B2%7D%7Bx%7D%20%2B%20%5Cfrac%7B1%7D%7Bx%20%2B%201%7D)
Find the Lowest common multiple
![\frac{x(x+ 1) - 2 (x+ 1)(x - 1) + x(x-1)}{x(x-1)(x+ 1)}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%28x%2B%201%29%20-%202%20%28x%2B%201%29%28x%20-%201%29%20%2B%20x%28x-1%29%7D%7Bx%28x-1%29%28x%2B%201%29%7D)
expand the brackets
![\frac{x^2 + x -2(x^2 -x + x -1) + x^2 -x}{x(x-1)(x+ 1)}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%5E2%20%2B%20x%20-2%28x%5E2%20-x%20%2B%20x%20-1%29%20%2B%20x%5E2%20-x%7D%7Bx%28x-1%29%28x%2B%201%29%7D)
![\frac{x^2+x - 2x^2 -2 + 2x + 2 + x^2 - x}{x(x+1) (x -1)}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%5E2%2Bx%20-%202x%5E2%20-2%20%2B%202x%20%2B%202%20%2B%20x%5E2%20-%20x%7D%7Bx%28x%2B1%29%20%28x%20-1%29%7D)
collect like terms
![\frac{2x}{x(x+ 1) (x-1)}](https://tex.z-dn.net/?f=%5Cfrac%7B2x%7D%7Bx%28x%2B%201%29%20%28x-1%29%7D)
Divide common terms
![\frac{2}{(x+ 1)(x - 1)}](https://tex.z-dn.net/?f=%5Cfrac%7B2%7D%7B%28x%2B%201%29%28x%20-%201%29%7D)
Thus, the expressions are simplified to 2x and ![\frac{2}{(x+ 1)(x - 1)}](https://tex.z-dn.net/?f=%5Cfrac%7B2%7D%7B%28x%2B%201%29%28x%20-%201%29%7D)
Learn more about algebraic expressions here:
brainly.com/question/4344214
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