Question 511471
13x +7(-3x-1) = -63
13x -21x -7 = -63
-8x = -56
x = 7
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Check the answer to be sure it is correct.
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13(7) + 7(-(3*7) -1) = ?
91 + 7(-22) = ?
91 - 154 = -63
Correct.
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Answer:  x=7
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Done.