Question

Y=-3x+2
Y=2x-3
How to solve these equations using substitution or elimination.

Answer 1

`Elimination\ method:\\\\ \left\{\begin{array}{ccc}y=-3x+2&|add\ 3x\ to\ both\ sides\\y=2x-3&|subtract\`


`subtitute\ value\ of\`

Answer 2

Substitution:

`y=-3x+2 \\ y=2x-3 \\ \\ \hbox{substitute -3x+2 for y in the 2nd equation and solve for x:} \\ -3x+2=2x-3 \\ -3x-2x=-3-2 \\ -5x=-5 \\ x=1 \\ \\ \hbox{substitue 1 for x in one of the equations and solve for y:} \\ y=2 * 1-3 \\ y=2-3 \\ y=-1 \\ \\ (x,y)=(1,-1)`

Elimination:

`y=-3x+2 \ \ \ |* (-1) \\ y=2x-3 \\ \\ -y=3x-2 \\ \underline{y=2x-3} \\ y-y=3x+2x-2-3 \\ 0=5x-5 \\ 5=5x \\ x=1 \\ \\ y=2 * 1-3=2-3=-1 \\ \\ (x,y)=(1,-1)`