Find the square of the number (-25), using the identity (a + b)2 = a2 + b2 + 2ab.

Asked by Topperlearning User | 4th Jun, 2014, 01:23: PM

Expert Answer:

We have:

(a + b)2 = a2 + b2 + 2ab

Taking, a = -20 and b = -5, we get

 

(-25)2 = {-20 + (-5)}2

         = (-20)2 + (-5)2 + 2(-20)(-5)

         = 400 + 25 + 200

         = 625

Answered by  | 4th Jun, 2014, 03:23: PM