3a divided by 5 - 6 = 3
\(\frac{3a}{5-6} = 3 \\ \frac{(5-6)3a}{5-6}=3(5-6) \\ 3a=3(-1) \\ a=-1\)
If you meant - 6 not in the denominator it's:
\(\frac{3a}{5}-6 = 3 \\ \frac{3a}{5}-6+6 = 3 + 6 \\ \frac{3a}{5} = 9 \\ \frac{(5)3a}{5} = (5)9 \\ 3a=45 \\ 3a/3=45/3 \\ a=15\)
\(\dfrac{3a}{5}-6 = 3\\ \dfrac{3a}{5}=9\\ \dfrac{a}{5}=3\\ a=15\)
