Question

Factor the following equations by product and sum. Then determine the solutions

Answer 1

Factor the following equations by product and sum.

Then determine the solutions

`a^2-121=0`

Step 1: Difference of two square

`\begin{gathered} a^2-121=0 \\ a^2-11^2=0 \\ (a-11)(a+11)=0 \end{gathered}`

Therefore the correct answer is

`(a-11)(a+11)`

Step 2: Then the solutions are

`\begin{gathered} a-11=0,a+11=0 \\ a=11,a=-11 \\ a=\pm11 \end{gathered}`