Question

How do you simplify `(d+7)/(d^2-49)`?

Answer 1

`=color(blue)(1/(d-7))`

Explanation:

As per property
`color(blue)(a^2-b^2=(a+b)(a-b)`

Expressing the denominator of the expression in the same manner:
`d^2- 49= d^2 -7^2 = color(blue)((d+7)(d-7)`

The expression can now be written as

`((d+7)) / color(blue)((d+7)(d-7)`

`=(cancel((d+7))) / color(blue)((d-7)cancel((d+7))`

`=color(blue)(1/(d-7))`