Solve for x
x=10
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-\frac{2}{5}x=-4
Subtract 4 from both sides. Anything subtracted from zero gives its negation.
x=-4\left(-\frac{5}{2}\right)
Multiply both sides by -\frac{5}{2}, the reciprocal of -\frac{2}{5}.
x=\frac{-4\left(-5\right)}{2}
Express -4\left(-\frac{5}{2}\right) as a single fraction.
x=\frac{20}{2}
Multiply -4 and -5 to get 20.
x=10
Divide 20 by 2 to get 10.
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Matrix
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Limits
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