Solve the system by substitution. y=-2x+1 -9x-2y=3

Answer 1

Plug the first equation into the second for y, since it is y=

-9x-2(-2x+1)=3 Distribute

-9x+4x-2=3 Combine like terms

-5x-2=3 Add 2 to both sides

-5x-2+2=3+2 Simplify

-5x=5 Divide both sides by -5

-5x/-5=5/-5 Simplify

x=-1

Next, solve for y using that first equation.

y=-2x+1

y=-2(-1)+1

y=2+1

y=3

(-1,3)