Question

if 2x+3x=8 and xy=4 then find the value of 4x²+9y²

Answer 1

Squaring on both sides
So
(2x+3y)²=(8)²
4x²+9y²+2*2x*3x=64
4x²+9y²+12xy=64
4x²+9y²+12*4=64
4x²+9y²=64-48
4x²+9y²=16



I hope this will help you
By DEVANSH