Solve this system by ELIMINATION!
9x-12y=15
-4x+4y=0​

x = -5

y = -5

Step-by-step explanation:

here's the solution :-

multiply equation (2) with 3

we get,

=》9x - 12y = 15

=》-12x + 12 y = 0

by adding the equations, :-

=》9x - 12y - 12 x + 12y = 15 + 0

=》-3x = 15

=》x = 15 ÷ -3

=》x = -5

putting the value of x as -5 in equation (2)

=》-4x + 4y = 0

=》( -4 × -5 ) + 4y = 0

=》20 + 4y = 0

=》4y = - 20

=》 y = -20 ÷ 4

=》y = -5

- (2, -7)

- lines r and s and lines t and u must be parallel