Question

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

Answer 1

Hlo
a- b = 7
ab = 9

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

( 7)^2 = a^2 + b^2 - 2 × 9

49 = a^2 + b^2 - 18

49 + 18 = a^2 + b^2

67 = a^2 + b^2

hope it helps.♥

Answer 2

Given:

a-b=7

ab=9

To find:

a²+b²

Solution:

We can find the solution in a few simple steps-

We know that the value of a²+b² can be found by using a property of (a-b)².

(a-b)² = a²+b²-2ab

On putting the values, we get

7²= a²+b² -2×9

49= a²+b² -18

49+18= a²+b²

a²+b² =67

Therefore, the value of a²+b² is 67.