7x + 3y = 30
-2x + 3y = 3....multiply by -1
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7x + 3y = 30
2x- 3y = -3 (result of multiplying by -1)
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9x = 27
x = 27/9
x = 3
7x + 3y = 30
7(3) + 3y = 30
21 + 3y = 30
3y = 30 - 21
3y = 9
y = 9/3
y = 3
solution is (3,3)
