It's hard to type this expression, the 5's 2's and -2 in red are exponents. Please help simplify: (2a5b2/4a5b-2) -4
Here's one I prepared earlier
$\displaystyle \frac{3a^4b^3}{9a^4b^{-1}}-3$
first cancelling the coefficents 3 and 9 we get
$\displaystyle \frac{a^4b^3}{3a^4b^{-1}}-3$
$\displaystyle a^4 $ is similar to both top and bottom as they cancel completely
$\displaystyle \frac{b^3}{3b^{-1}}-3$
Now lets take care of the b terms with the rule $\displaystyle a^m\div a^n = a^{m-n}$
$\displaystyle \frac{b^{3-(-1)}}{3}-3$
finally
$\displaystyle \frac{b^4}{3}-3$
and making a common denominator of 3 in both terms gives
$\displaystyle \frac{b^4-9}{3}$
Now use this example to finish yours!