Question

Add. Simplify by removing factors of 1if possible
28zx + z-7x
----- -----
z^2-49x^2 z+7x

Answer 1

First factor bottom
(z-7x)(z+7x)
This shares the (z+7x) in other denominator
so common denominator will be (z-7x)(z+7x)
multiply 2nd fraction by (z-7x) on top and bottom
\[=\frac{28xz +(z-7x)(z-7x)}{(z-7x)(z+7x)}\]
expand the top and add like terms
\[=\frac{z^{2} + 49x^{2}}{(z-7x)(z+7x)}\]
top will not factor
so this is answer