\({9 \over 4x}-{8 \over 4x}={1 \over 4x}\)

\({4 \over a}-{9 \over 3a}={12 \over 3a}-{9 \over 3a}={3 \over 3a}={1 \over a}\)

\({4 \over 9a}-{7 \over 3b}={4b \over 9ab}-{21a \over 9ab}={4b-21a \over 9ab}\)

\(4-{2 \over 9x}={4 \over 1}-{2 \over 9x}={36x \over 9x}-{2 \over 9x}={36x-2 \over 9x}\)

\(7p-{5 \over 2p}={7p \over 1}⋅{2p \over 2p}-{5 \over 2p}={14p^2 \over 2p}-{5 \over 2p}={14p^2-5 \over 2p}\)

\({6x \over y}-{3 \over 8y}={48x \over 8y}-{3 \over 8y}={48x-3 \over 8y}\)

\({7b \over 8a}+{4a \over 6b}={21b^2 \over 24ab}+{16a^2 \over 24ab}={16a^2+21b^2 \over 24ab}\)

\({8a \over a}={8 \over 1}=8\)

\({x \over 6x}={1 \over 6}\)

\({15p \over 20p}=\frac{3}{4}\)

\({-24x \over -3x}=8\)

\({-10xy \over -45xz}={2y \over 9z}\)

\({14q \over 16pq}={7 \over 8p}\)

\({-20abc \over 5bc}=-4a\)

\({6ab \over b}+{3ac \over c}=6a+3a=9a\)

\({2 \over x}⋅-{6 \over y}=-{12 \over xy}\)

\({p \over 8}⋅{7 \over q}={7p \over 8q}\)

\({8 \over 3}⋅x={8x \over 3}\)

\({4 \over a}:{5 \over b}={4 \over a}⋅{b \over 5}={4b \over 5a}\)

\({8 \over 7}:a={8 \over 7}:{a \over 1}={8 \over 7}⋅{1 \over a}={8 \over 7a}\)