Solve for x
x=-35
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x\times 0.4-x=21
Subtract x from both sides.
-0.6x=21
Combine x\times 0.4 and -x to get -0.6x.
x=\frac{21}{-0.6}
Divide both sides by -0.6.
x=\frac{210}{-6}
Expand \frac{21}{-0.6} by multiplying both numerator and the denominator by 10.
x=-35
Divide 210 by -6 to get -35.
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