Factor 25 out of 25a^2−100.
Factor 25 out of 25a^2.
25(a^2)−100
Factor 25 out of −100.
25a^2+25⋅−4
Factor 25 out of 25a^2+25⋅−4.
25(a^2−4)
Rewrite 4 as 2^2.
25(a^2−2^2)
Factor.
Since both terms are perfect squares, factor using the difference of squares formula, a^2−b^2=(a+b)(a−b) where a=a and b=2.
25((a+2)(a−2))
Remove unnecessary parentheses.
25(a+2)(a−2)
I believe this is correct.
