# SOLUTION: 7x+3y=4, 5x+9y=10

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Question 167608: 7x+3y=4, 5x+9y=10
Found 2 solutions by Mathtut, jim_thompson5910:
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
We'll use substitution. After moving 3*y to the right, we get:
, or . Substitute that
into another equation:
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error_location: 101

You can put this solution on YOUR website!

Multiply the both sides of the first equation by -3.

Distribute and multiply.

So we have the new system of equations:

Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:

Group like terms.

Combine like terms. Notice how the y terms cancel out.

Simplify.

Divide both sides by to isolate .

Reduce.

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Now go back to the first equation.

Plug in .

Multiply.

Multiply EVERY term by the LCD to clear the fraction.

Multiply.

Combine like terms on the right side.

Divide both sides by to isolate .

Reduce.

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