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Use substitution to solve for y in the system of equations.

5x + y = 6
3x - 3y = 18


A. y = -4

B. y = 8

C. y = 16

D. y = 2

User Jodee
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2 Answers

5 votes
a -4 is the answer i am for sure i am right
User Mentor Reka
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7.6k points
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Equation 1: 5x + y = 6
Equation 2: 3x - 3y = 18

Multiply all of equation 1 by 3.

1) 3(5x+y=6)

1) 15x + 3y = 18
2) 3x - 3y = 18

Add equations together.

18x = 36

Divide both sides by 18.

x = 2

Plug in 2 for x in first equation.

5x + y = 6

5(2) + y = 6

10 + y = 6

Subtract 10 from both sides.

y = 6 - 10

y = -4

So, your answer is a) -4

~Hope I helped!~
User Fahime Ghasemi
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