Question

If 3x + 2y = 12 and xy = 6, find the value of 9x^2+4y^2 , in full details

Answer 1

Answer:

(3x+2y)^2=(12)^2

9x^2+4y^2+12xy=145

9x^2+4y^2=145-12xy

putting the value of xy

9x^2+4y^2=145-12×6

=145-72

=73

Answer 2

Step-by-step explanation:

3x+2y=12.........eq1

Xy=6

X=6/y

Sub x=6/y.in eq1

3(6/y)+2y=12

18/y+2y=12

18y+2y^2=12y

2y^2=-6y

2y^2+6y=0

2y(y+3)=0

2y=0 (or) y+3=0

Y=o (or) y=-3

Sub, y values in eq1

If y=0 of y= - 3

3x+2(0)=12 3x+2(-3)=12

3x=12 3x-6=12

X=4 (or) 3x=18=>6

=>9x^2+4y^2 (or) =>9x^2+4y^2

=>9(4)^2+4(0)^2 =>9(6)^2+4(-3)^2

=>9(16)+0 =>9(36)+4(9)

=>144 =>324+36

=>360