Solve for x
x=194.5
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81=0.4\left(x+8\right)
Variable x cannot be equal to -8 since division by zero is not defined. Multiply both sides of the equation by x+8.
81=0.4x+3.2
Use the distributive property to multiply 0.4 by x+8.
0.4x+3.2=81
Swap sides so that all variable terms are on the left hand side.
0.4x=81-3.2
Subtract 3.2 from both sides.
0.4x=77.8
Subtract 3.2 from 81 to get 77.8.
x=\frac{77.8}{0.4}
Divide both sides by 0.4.
x=\frac{778}{4}
Expand \frac{77.8}{0.4} by multiplying both numerator and the denominator by 10.
x=\frac{389}{2}
Reduce the fraction \frac{778}{4} to lowest terms by extracting and canceling out 2.
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