# How do you combine (x-3)/ (30x+5) - 2/ (18x+3)?

$\frac{x - 3}{30 x + 5}$ = $\frac{x - 3}{5 \left(6 x + 1\right)}$
$\frac{2}{18 x + 3}$ = $\frac{2}{3 \left(6 x + 1\right)}$
Notice that the least common denominator is $5 \cdot 3 \cdot \left(6 x + 1\right) = 15 \left(6 x + 1\right)$. This means that we have to multiply the first term by $3$ and the second term by $5$.
This gives: $\frac{3 \left(x - 3\right) - 2 \cdot 5}{15 \left(6 x + 1\right)}$ = $\frac{3 x - 19}{15 \left(6 x + 1\right)}$ = $\frac{3 x - 19}{90 x + 15}$