Question

if 2a+3b=7 & ab=2, find 4a² +9b²

Answer 1

2a+3b=7

(2a+3b)^2=49

4a^2+9b^2+12ab=49

4a^2+9b^2+12(2)=49

4a^2+9b^2=49-24

4a^2+9b^2=25

therefore

4a^2+9b^2 = 25