Question

if ab=12,a-b=8, then find the value of a²+b²

Answer 1

(a-b)² = a² + b² - 2ab
=> (a-b)² + 2ab = a²+b²
=> (8)² +2×12 = a²+b²
=> 64+24 = 88 = a²+b²

Answer 2

a²+b²=a²+b²-2ab+2ab
a²+b²=(a-b)²+2ab
a²+b²=8²+2(12)
a²+b²=64+24
a²+b²=88