Hello!
You put in the know values for x or y
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(-6, ?)
We know that x is -6
6y + 5(-6) = -30
Combine like terms
6y + -30 = -30
Add 30 to both sides
6y = 0
y = 0
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(?, 5)
We know that y is 5
6(5) + 5x = -30
Combine like terms
30 + 5x = -30
Subtract 30 from both sides
5x = -60
Divide both sides by 5
x = -12
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The answers are (-6, 0) and (-12, 5)
Hope this helps!