Solve for x
x=4
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20=x\times 3+x+4
Variable x cannot be equal to any of the values -4,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+4\right), the least common multiple of x^{2}+4x,x+4,x.
20=4x+4
Combine x\times 3 and x to get 4x.
4x+4=20
Swap sides so that all variable terms are on the left hand side.
4x=20-4
Subtract 4 from both sides.
4x=16
Subtract 4 from 20 to get 16.
x=\frac{16}{4}
Divide both sides by 4.
x=4
Divide 16 by 4 to get 4.
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