Question

1. Solve the system using substitution

x+y=8
y=3x
A.(4,12)
B.(2,6)
C.(1/2,2/3)
D.(-4,-12)

Answer 1

x+y=8
y=3x

You would want to substitute the y for the 3x
x+3x=8

You can now add the x with the 3x to get 4x
4x=8

Now divide the 4 on both side to solve for x
x=2

Now to solve for y just substitute the x for the 2
y=3(2)

Now multiply the 3 and the 2 to solve for y.
y=6

So your corrct answer is B:(2,6)