[Given]
{ x + y = 6
{ x = y + 4
[Plug-in our x value & solve]
[Given] x + y = 6
[ Plug-in] (y + 4) + y = 6
[Distribute] y + 4 + y = 6
[Combine like terms] 2y + 4 = 6
[Subtract 4 from both sides] 2y = 2
[Divide both sides by 2] y = 1
[Answer]
Third option - (5, 1)
-> You do not need to solve for x since this is the only option that has y = 1, but to solve for x we would do y + 4 = 1 + 4 = 5, so this answer fully checks correctly
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- Heather