Solve for x
x=7
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13x-1=90
Combine 5x and 8x to get 13x.
13x=90+1
Add 1 to both sides.
13x=91
Add 90 and 1 to get 91.
x=\frac{91}{13}
Divide both sides by 13.
x=7
Divide 91 by 13 to get 7.
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