Question

Use the identity
(a-b)²=a²+2ab+b²
Evaluate the following
a)126² b)775²

Answer 1

Step-by-step explanation:

a)126^2 can be written as (130-4)^2

we know that (a-b)^2=a^2+b^2-2ab

so,

130^2+4^2-2*130*4

16900+16-1040

15876

b)775^2cqn be written as (780-5)^2

using identity

780^2+5^2-2*780*5

600625

hope this will help you plzz mark as brainliest

Answer 2

Step-by-step explanation:

(a) 126²

(120 + 6)²

(120)² + 2×120×6 + (6)²

14400 + 1440 + 36

14436 + 1440

15876

(b) 775²

(770 + 5)²

(770)² + 2×770×5 + (5)²

592900 + 77000 + 25

669900 +25

669925