Answer:
A. (x - 5)(x - 5)
Step-by-step explanation:
We will do this the old fashioned way...just plain old factoring.
This polynomial is of the form
The product of a and c have to add up to equal the "middle" term, -10.
a = 1, b = -10, c = 25
a * c = 1 * 25 = 25
Now we need the factors of 25 to find the combination of factors that will result in a -10. The factors of 25 are: 1, 25 and 5, 5
5 and 5 add up to be 10, but since we need a -10, we will use -5 and -5. The product of -5 * -5 = 25, so we are not messing anything up by using the negative 5.
Putting them in order in standard form we have
Factor by grouping:
There is an x common to both terms in the first set of parenthesis, so we will factor that out; there is a 5 common to both terms in the second set of parenthesis, so we will factor that out:
x(x - 5) - 5(x - 5)
NOW what's common in both terms is the (x - 5) so we factor THAT out, and what's left gets grouped together:
(x - 5)(x - 5)