SOLUTION: 2x-3y=7 y=3x-7 substitution equations i am stuck please help

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Question 71964This question is from textbook algebra
: 2x-3y=7
y=3x-7 substitution equations
i am stuck please help
This question is from textbook algebra

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the system of equations by substitution:
1) 2x-3y+=+7
2) y+=+3x-7 Substitute this for y in equation 1) and solve for x.
1a) 2x-3%283x-7%29+=+7 Simplify and solve for x. Apply the distributive property.
2x-9x%2B21+=+7 Notice the change of sign (- to +) on the last term! Now combine like-terms.
-7x+%2B+21+=+7 Subtract 21 from both sides.
-7x+=+-14 Divide both sides by -7.
x+=+2 Now substitute this value of x into either one of the two original equations and solve for y. Using equation 2):
y+=+3%282%29-7
y+=+6-7
y+=+-1
The solution is: (2, -1)
Here's the graph:
graph%28300%2C200%2C-5%2C5%2C-5%2C5%2C%282%2F3%29x-%287%2F3%29%2C3x-7%29
Notice that the solution to this system of equations is the point of intersection of the two lines represented by the two equations.