Question

2a+b=12 ab=15 find 8a cube +b cube

Answer 1

Step-by-step explanation:

2a+b=12......(1)

ab=15..........(2)

in equation 1

2a+b=12

or, b=12-2a......(3)

now putting the value of b in equation (1)

a(12-2a)=15

or, 12a-2a^2 =15

or,2a^2-12a+15=0

by quadratic equation

find the value of (a) then putting in equation (3)