 # Solving System of Equations by Multiplication and then Addition or Subtraction

Objective: I know how to solve system of equations by multiplication and then addition or subtraction.

Sometimes, none of the coefficients of the variables are opposites or equal. However, it may be possible to multiply one of the equations with a number that will then make the coefficients of one of the variables opposites or equal. We can then add or subtract the equations to eliminate one of the variables.

Look up the lesson on Solving System of Equations if you need help on solving system of equations.

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
Solve each equation.

4x + 2y = - 38
16x + 4y = - 124
Answer: x = , y =

5x - 2y = 39
20x - 4y = 148
Answer: x = , y =

4x + 5y = 74
- 12x + 2y = - 52
Answer: x = , y =

5x + 4y = - 19
2x - 8y = - 46
Answer: x = , y =

4x - 3y = - 35
12x - 5y = - 69
Answer: x = , y =

3x + 3y = - 51
9x + 2y = - 97
Answer: x = , y =

- 4x + 2y = 4
- 2x + 4y = 26
Answer: x = , y =

5x + 2y = -1
3x + 4y = - 9
Answer: x = , y =

- 2x - 3y = - 5
- 3x - 9y = - 12
Answer: x = , y =

2x + 2y = 0
- 3x + 4y = - 14
Answer: x = , y =

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