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Solve the system by either the addition method or the substitution method.

x + 3y = 1
4x + 4y = -12

1 Answer

3 votes

Answer:x = - 5

y = 2

Explanation:

The given system of simultaneous equations is expressed as

x + 3y = 1 - - - - - - - - - - - - - -1

4x + 4y = -12 - - - - - - - - - - - 2

We want to eliminate x. Multiplying equation 1 by 4 and equation 2 by 1, it becomes

4x + 12y = 4

4x + 4y = - 12

Subtracting the second equation from the first equation, it becomes

8y = 16

y = 16/8 = 2

Substituting y = 2 into equation 1, it becomes

x + 3 × 2 = 1

x + 6 = 1

x = 1 - 6 = - 5

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