x210x+?=(??)2

1 Answer
Oct 13, 2017

x210x+25=(x5)2

Explanation:

We want to add a number on the left so we get a perfect square on the right. A quick way to do this is to add (b2)2, in this case that is:

(102)2=25

So:

x210x+25=(??)2

Factoring we get:

x210x+25=(x5)2