Solve for x
x=4
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4\times 720=9x\times 80
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 36x, the least common multiple of 9x,4.
2880=9x\times 80
Multiply 4 and 720 to get 2880.
2880=720x
Multiply 9 and 80 to get 720.
720x=2880
Swap sides so that all variable terms are on the left hand side.
x=\frac{2880}{720}
Divide both sides by 720.
x=4
Divide 2880 by 720 to get 4.
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