SOLUTION: how do i do this problem by using substitution 4x+4y=24 y=6x+20

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Question 826760: how do i do this problem by using substitution
4x+4y=24
y=6x+20
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Since y is solved for in eqn 2, sub for y in eqn 1.
4x+4y=24
y=6x+20
---------
4x+4y=24 --> x + y = 6

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

4x%2B4y=24+....eq.1
y=6x%2B20....eq.2
______________________
4x%2B4y=24+....eq.1.............substitute y from eq.2
4x%2B4%286x%2B20%29=24+..........solve for x
4x%2B24x%2B80=24+
28x=24-80+
28x=-56+
x=-56%2F28+
highlight%28x=-2%29+
now, go back to eq.2 and find y
y=6x%2B20....eq.2.........plug in value of x
y=6%28-2%29%2B20
y=-12%2B20
highlight%28y=8%29