SOLUTION: solve the following systems of equations algebraic ally and check : 3x+y=3 y=2x-7

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Question 1012695: solve the following systems of equations algebraic ally and check :
3x+y=3
y=2x-7

Found 2 solutions by Alan3354, fractalier:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
3x+y=3
y=2x-7
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Sub for y in the 1st eqn
3x + (2x-7) = 3
5x = 10
x = 2
y = -3

Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
For this system, I would recommend the substitution method...
3x+y=3
y=2x-7
Let's substitute the second equation into the first and get
3x + (2x - 7) = 3
5x - 7 = 3
5x = 10
x = 2
and then
y = 2(2) - 7 = -3
The answer is (2, -3).
Checking the first equation gives
3(2) + (-3) = 3
6 - 3 = 3
3 = 3 checks!