Question

Solve by the substitution method

y=3x-12
2x-3y=-13

Answer 1

y=3x-12......(1)
2x-3y=-13...(2)

substitute y in eqn 2
2x-3(3x-12)=-13
2x-9x+36=-13
collect like terms
36+13=9x-2x
49=7x
x=49/7=7
x=7
solve for y in eqn 1 where x=7
y=3(7)-12
y=21-12=9
y=9

Answer 2

y=3x-12
2x-3y=-13
substitute y=3x-12 into 2x-3y=-13

2x-3y=-13
2x-3(3x-12)=-13
2x - 9x + 36 = -13
-7x = -49
x = 7

y=3x-12 = y=3(7) -12 = 21 - 12 = 9

answer
solution
x = 7 and y = 9