SarkariPYQ

SSC CHSL 2020 PYQ — Question 54

SSC CHSL - 12th October 2020 - Shift 2 • Quantitative Aptitude • Q54

Back to paper

If a + b = 11 and ab = 15, then a2 + b2 is equal to:

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e 91.

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

Given, a + b = 11

ab = 15

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

(11)2 = a2 + b2 + 2(15)

121 = a2 + b2 + 2(15)

a2 + b2 = 121 - 30 = 91