Solve for x
x=3
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10\left(4x-8\right)=\left(x+7\right)\times 4
Variable x cannot be equal to -7 since division by zero is not defined. Multiply both sides of the equation by 30\left(x+7\right), the least common multiple of 3x+21,30.
40x-80=\left(x+7\right)\times 4
Use the distributive property to multiply 10 by 4x-8.
40x-80=4x+28
Use the distributive property to multiply x+7 by 4.
40x-80-4x=28
Subtract 4x from both sides.
36x-80=28
Combine 40x and -4x to get 36x.
36x=28+80
Add 80 to both sides.
36x=108
Add 28 and 80 to get 108.
x=\frac{108}{36}
Divide both sides by 36.
x=3
Divide 108 by 36 to get 3.
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