Chapter 4 - Section 4.2 - Solving Systems of Linear Equations by the Substitution Method - Exercise Set - Page 300: 10

{(-7,1)}

-x+3y=10 10=-x+3y 10+x=3y x=3y-10 Plug this value for x into the other equation. 2x+8y=-6 2(3y-10)+8y=-6 2(3y)-2(10)+8y=-6 6y-20+8y=-6 6y+8y-20=-6 14y-20=-6 14y=-6+20 14y=14 y=$\frac{14}{14}$ y=1 Plug this back into the first equation. x=3y-10 x=3(1)-10 x=3-10 x=-7 Therefore the solution is {(-7,1)}