## Algebra: A Combined Approach (4th Edition)

Step 1: $(6-2i)(6+2i)$ Step 2: $6(6+2i)-2i(6+2i)$ Step 3: $36+12i-12i-4i^{2}$ Step 4: $36-4i^{2}$ Step 5: Since $i^{2}=-1$, the expression becomes $36-4(-1)$ which is equal to 40