SOLUTION: Please help me. I really do not understand this. Thanks! Add simplify if possible 6z/z^2-36+z/z-6 (these are factions not dividing) Factor completely 25s^2-121

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Please help me. I really do not understand this. Thanks! Add simplify if possible 6z/z^2-36+z/z-6 (these are factions not dividing) Factor completely 25s^2-121      Log On


   

Question 238557: Please help me. I really do not understand this. Thanks!
Add simplify if possible
6z/z^2-36+z/z-6 (these are factions not dividing)
Factor completely
25s^2-121
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Add simplify if possible
;
%286z%29%2F%28z%5E2-36%29 + z%2F%28z-6%29
The 1st denominator is the "difference of squares" and can be factored to
%286z%29%2F%28%28z%2B6%29%28x-6%29%29 + z%2F%28z-6%29
(z-6)(z+6) would be the common denominator so we have:
%286z+%2B+z%28z%2B6%29%29%2F%28%28z%2B6%29%28x-6%29%29 = %286z+%2B+z%5E2+%2B+6z%29%2F%28%28z%2B6%29%28x-6%29%29 = %28z%5E2+%2B+12z%29%2F%28%28z%2B6%29%28x-6%29%29 = z%28z+%2B+12%29%2F%28%28z%2B6%29%28x-6%29%29
:
:
Factor completely
25s^2 - 121
Both 25 and 121 are perfect squares, you should recognize this as the "difference of squares"
(5s - 11) (5s + 11)
:
Check this by FOILing
25s^2 + 55s - 55s - 121
Middle terms cancel
25s^2 - 121