SOLUTION: How do you solve by substitution of linear equation? 2x+y=9 y=x-3

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Question 214189: How do you solve by substitution of linear equation?
2x+y=9
y=x-3
Found 2 solutions by drj, Alan3354:
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve by substitution of linear equation?
2x%2By=9
y=x-3

The following steps solves the equation by substitution.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++2%5Cx+%2B+1%5Cy+=+9%2C%0D%0A++++-1%5Cx+%2B+1%5Cy+=+-3+%29%0D%0A++We'll use substitution. After moving 1*y to the right, we get:
2%2Ax+=+9+-+1%2Ay, or x+=+9%2F2+-+1%2Ay%2F2. Substitute that
into another equation:
-1%2A%289%2F2+-+1%2Ay%2F2%29+%2B+1%5Cy+=+-3 and simplify: So, we know that y=1. Since x+=+9%2F2+-+1%2Ay%2F2, x=4.

Answer: system%28+x=4%2C+y=1+%29.



The solution is x=4 and y =1 or the point (4,1)

I hope the above steps were helpful.

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And good luck in your studies!

Respectfully,
Dr J

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve by substitution of linear equation?
2x+y=9
y=x-3
-----------
The 2nd eqn has y isolated, so sub for y into the 1st eqn.
2x+y=9
2x + (x-3) = 9
3x - 3 = 9
3x = 12
x = 4
-----
y = x-3 = 4-3
y = 1