Question

if 2x+3y=8, xy=-2 then find 4x^2+9y^2

Answer 1

Answer:

88

Step-by-step explanation:

2x+3y=8          (1)

xy=-2               (2)

by squaring on both sides of equation 1

(2x+3y)²=8²

4x²+9y²+12xy=64

(given that xy=-2)

4x²+9y²-12*2=64        

4x²+9y²=64+24=88