6r + 7 = 13 + 7r
r = -6
13 − 4x = 1 − x
x = 4
4n − 40 = 7(−2n + 2)
n = 3
−7x − 3x + 2 = −8x − 8
x = 5
3(1 − 3x) = 2(−4x + 7)
x = -11
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