Question

if 2 X + 3 Y = 8 and xy = 2 find 4 x square + 9 y square​

Answer 1

Answer:

22 or 18

Explanation:

2x + 3y = 8

xy = 2

so, x = 2/y

2(2/y) + 3y = 8

4 + 3y^2 = 8y

3y square -8y +4 = 0

3y square -6y -2y +4 = 0

3y(y -2) -2(y -2)= 0

(3y-2)(y-2) = 0

so, the y = 2/3 Or y = 2

if y = 2/3 so x = 3

if y = 2 so x = 1

4x square + 9y square

if x = 3 and y = 2/3

4(3) + 9(2/3)

12 + 6 = 18

Or

if x=1 and y =2

4(1) + 9(2)

4 + 18 = 22