Solve for x
x=-5
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\frac{1}{7}x=-\frac{8}{21}-\frac{1}{3}
Subtract \frac{1}{3} from both sides.
\frac{1}{7}x=-\frac{8}{21}-\frac{7}{21}
Least common multiple of 21 and 3 is 21. Convert -\frac{8}{21} and \frac{1}{3} to fractions with denominator 21.
\frac{1}{7}x=\frac{-8-7}{21}
Since -\frac{8}{21} and \frac{7}{21} have the same denominator, subtract them by subtracting their numerators.
\frac{1}{7}x=\frac{-15}{21}
Subtract 7 from -8 to get -15.
\frac{1}{7}x=-\frac{5}{7}
Reduce the fraction \frac{-15}{21} to lowest terms by extracting and canceling out 3.
x=-\frac{5}{7}\times 7
Multiply both sides by 7, the reciprocal of \frac{1}{7}.
x=-5
Cancel out 7 and 7.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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