Question

Solve the system by the substitution method.

x - 3y = -4
y = -3x + 8

Select the correct choice below and fill in any answer boxes present in your choice.

A.The solution is ___ ​(Type an ordered​ pair.)
B.There are an infinitely many solutions.
C.There is no solution.

Answer 1

(2,2)

Explanation:

Given equations

x-3y=-4-------------------------------(1)

y=-3x+8.------------------------------(2)

Substitute 2 in 1. This means use the value of y in equation 1, to replace y

x-3(-3x+8)=-4------------------open brackets

x+9x-24=-4---------------------collect like terms

10x=-4+24

10x=20---------------------------divide by 10 both sides to get value of x

10x/10=20/10=2

x=2------------------------------use value of x in equation (2) to get value of y

y=-3x+8

y=-3(2)+8

y=-6+8=2

solutions

x=2, y=2