Solve for x
x=12
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0.3x+8.4=x
Use the distributive property to multiply x+28 by 0.3.
0.3x+8.4-x=0
Subtract x from both sides.
-0.7x+8.4=0
Combine 0.3x and -x to get -0.7x.
-0.7x=-8.4
Subtract 8.4 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-8.4}{-0.7}
Divide both sides by -0.7.
x=\frac{-84}{-7}
Expand \frac{-8.4}{-0.7} by multiplying both numerator and the denominator by 10.
x=12
Divide -84 by -7 to get 12.
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