Solve for a
a=-10
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a+7=0.3a
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by a.
a+7-0.3a=0
Subtract 0.3a from both sides.
0.7a+7=0
Combine a and -0.3a to get 0.7a.
0.7a=-7
Subtract 7 from both sides. Anything subtracted from zero gives its negation.
a=\frac{-7}{0.7}
Divide both sides by 0.7.
a=\frac{-70}{7}
Expand \frac{-7}{0.7} by multiplying both numerator and the denominator by 10.
a=-10
Divide -70 by 7 to get -10.
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Limits
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