So we want to simplify the equation (x-5)^2:
What we wanna do is to write it out completely or use the formula if you know it:
1. The first way is the foil method:
(x-5)(x-5), we want to multiply each term by the other two terms:
x times x, x times -5, -5 times x, and -5 times -5
x^2-5x-5x+25
Then we can simplify to:
x^2 - 10x + 25
2. The next way is just to use the formula (x-b)^2 = x^2-2xb+b^2
In both ways, you get x^2 -10x + 25
The answer is the third option
