Question

Help - I need a reply from someone who understands rational expressions

Answer 1

expressions such as
\[(x+y) TOP / (3x-18) BOT / Div By (X^2-11X+30) TOP / BOT (X^2 -81)\] tHE ANSWER SIMPLIFIED IS (X-5) TOP/BOT (3 (X-9)) My question is, how can I mathematically check this answer?

Answer 2

use \frac{top}{bot} to make a fraction in equation mode.
\[ \frac{top}{bot} \]
There are a couple of ways to check your answer.
1) type the original expression into wolfram
2) double check your factors (for example, you had to factor (x^2-81) . multiply out the factors to make sure you get (x^2-81) )
3) select random numbers for x and y. plug them into the original equation and get a number. ditto for your simplified version. You must get the same answer.