Question

Please help on this one?

Answer 1

`D. \: \frac{10 {x}^(2) + 50x}{ {x}^(2) - 49 }`

Explanation:

The given rational expression is

`(x + 5)/(x + 7) \cdot (10x)/(x - 7)`

We multiply to obtain:

`(10x(x + 5))/((x + 7)(x - 7))`

Expand the numerator using the distributive property and the denominator using difference of two squares to get:

`\frac{10 {x}^(2) + 50x }{ {x}^(2) - {7}^(2) }`

This simplifies to

`\frac{10 {x}^(2) + 50x}{ {x}^(2) - 49 }`