Question

if x + y = 12 and xy = 14, find the value of x2 + y2​

Answer 1

x+y = 12 and xy = 14

According to condition,

x + y = 12

or, (x+y)² = 12² (squaring both sides)

or, x²+y²+2xy = 144

or, x²+y²+(2×14) = 144

or, x²+y²+28 = 144

or, x²+y² = 144-28

or, x²+y² = 116

Hence, the value of x²+y² is 116.