Solve for a
a = \frac{43}{21} = 2\frac{1}{21} \approx 2.047619048
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\frac{49}{21}-\frac{6}{21}=a
Least common multiple of 3 and 7 is 21. Convert \frac{7}{3} and \frac{2}{7} to fractions with denominator 21.
\frac{49-6}{21}=a
Since \frac{49}{21} and \frac{6}{21} have the same denominator, subtract them by subtracting their numerators.
\frac{43}{21}=a
Subtract 6 from 49 to get 43.
a=\frac{43}{21}
Swap sides so that all variable terms are on the left hand side.
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