Question

a-b=7 and ab=9 then find a2+b2

Answer 1

Answer:

$a^2 + b^2 = 67$

Step-by-step explanation:

We know that

$(a - b)^2 = a^2 + b^2 - 2ab$

Given:

(a - b) = 7

ab = 9

Substituting the values in the  identity,

$(7)^2 = a^2 + b^2 - 2(9)$

$49 = a^2 + b^2 - 18\\a^2 + b^2 = 49 + 18\\a^2 + b^2 = 67$