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X+3y=18

Complete the table of order pairs

1 Answer

4 votes

Answer:

x−y=−2

4x−y=4

To solve a pair of equations using substitution, first solve one of the equations for one of the variables. Then substitute the result for that variable in the other equation.

x−y=−2,4x−y=4

Choose one of the equations and solve it for x by isolating x on the left hand side of the equal sign.

x−y=−2

Add y to both sides of the equation.

x=y−2

Substitute y−2 for x in the other equation, 4x−y=4.

4(y−2)−y=4

Multiply 4 times y−2.

4y−8−y=4

Add 4y to −y.

3y−8=4

Add 8 to both sides of the equation.

3y=12

Divide both sides by 3.

y=4

Substitute 4 for y in x=y−2. Because the resulting equation contains only one variable, you can solve for x directly.

x=4−2

Add −2 to 4.

x=2

The system is now solved

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