Question

10. Compute the value of 9x + 4y if xy = 6 and 3x + 2y = 12.​

Answer 1

Answer:

e

30

Step-by-step explanation:

x = 6/y

3×6/y + 2y = 12

2y^2 -12y + 18 = 0

y = 3

x = 6/3 = 2

9×2 + 4×3 = 30

e

Answer 2

Answer:

xy=6

x=6/y

3x+2y=12

put the value of x

3×6/y+2y=12

18/y+2y=12

18+2y^2=12y

2y^2-12y+18=0

2(y^2-6y+9)=0

y^2-6y+9=0

factor is (y-3),(y-3)

then value of y =3,3

put the value of y

x=6/3

x=2

now equation

9x+4y

9×2+4×3

18+12

30