Answer:
B
Step-by-step explanation:
Expand (x+5)^2 through binomial expansion and you get x^2+10x+25.
Break up the problem into little pieces like (x-5)(x+5) and 10(x+5)
Solve the first piece (x-5)(x+5) by doing something like FOIL.
x^2-25
Do the second piece
10x+50
When you add them together, it becomes x^2+10x+25, and (x+5)^2=(x-5)(x+5)+10(x+5).
