Question

Solve the system of equations using the substitution method.

y=2x-1

y=3x+3

Choose the ordered pair that solves both equations.


(4,7)

(2,5)

(-4, -9)

(-1,3)

Answer 1

(-4,-9)

Explanation:

both equations are equal to y, y=2x-1 and y=3x+3, which makes them equal to eachother, 2x-1=3x+3

2x-1=3x+3, make x the subject:

subtract 2 (-2) from both sides

-2x+2x-1=3x+3-2x

-1=x+3

subtract 3 (-3) from both sides

-3-1=x+3-3

-4=x

therefore, x=-4

substitute x into any 1 of the original equation to get y:

y=2x-1

y=2(-4)-1

y=-8-1

y=-9