solve the system of liner equations.

Question

-9x+6y=-30

-12x+9y=-30

Answer 1

Given equations are -9x + 6y = -30 ==>1

                                 -12x + 9y = -30 ==>2

Multiply equation 1 with 9 and equation 2 with 6

(-9x + 6y = -30)9 ==>1

(-12x + 9y = -30)6 ==>2

-81x + 54y = -270 ==>3

-72x + 54y = -180 ==>4

Substract equation 3 from equation 4

-81x + 54y = -270 ==>3

-72x + 54y = -180 ==>4

(+)   (-)          (+)

-9x           = -90

-9x = -90

x = -90/-9

x = 10

Substitute x value in equation 1

-9x + 6y = -30

-9(10) + 6y = -30

-90 + 6y = -30

6y = -30 + 90

6y = 60

y = 10

Therefore the solution of the given system of linear equations is x = 10 and y = 10