\({7 \over 4x}+{6 \over 4x}={13 \over 4x}\)

\({5 \over x}+{2 \over 8x}={40 \over 8x}+{2 \over 8x}={42 \over 8x}={21 \over 4x}\)

\({9 \over 4p}+{2 \over 8q}={18q \over 8pq}+{2p \over 8pq}={18q+2p \over 8pq}={9q+p \over 4pq}\)

\(9-{3 \over 4a}={9 \over 1}-{3 \over 4a}={36a \over 4a}-{3 \over 4a}={36a-3 \over 4a}\)

\(5a+{9 \over 8a}={5a \over 1}⋅{8a \over 8a}+{9 \over 8a}={40a^2 \over 8a}+{9 \over 8a}={40a^2+9 \over 8a}\)

\({4x \over y}-{3 \over 2y}={8x \over 2y}-{3 \over 2y}={8x-3 \over 2y}\)

\({8y \over 4x}+{9x \over 6y}={24y^2 \over 12xy}+{18x^2 \over 12xy}={18x^2+24y^2 \over 12xy}={3x^2+4y^2 \over 2xy}\)

\({3a \over a}={3 \over 1}=3\)

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

\({-16p \over -36p}=\frac{4}{9}\)

\({12p \over 4p}=3\)

\({-35xy \over 45xz}=-{7y \over 9z}\)

\({-9y \over 21xy}=-{3 \over 7x}\)

\({40abc \over -5bc}=-8a\)

\({7ab \over b}+{5ac \over c}=7a+5a=12a\)

\({9 \over x}⋅-{3 \over y}=-{27 \over xy}\)

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

\(-{7 \over 5}⋅a=-{7a \over 5}\)

\({3 \over x}:{2 \over y}={3 \over x}⋅{y \over 2}={3y \over 2x}\)

\({1 \over 5}:a={1 \over 5}:{a \over 1}={1 \over 5}⋅{1 \over a}={1 \over 5a}\)

\({7x \over 4}+{x-9 \over 5}={35x \over 20}+{4(x-9) \over 20}={35x+4(x-9) \over 20}={39x-36 \over 20}\)

\({5b \over a}⋅{a+8 \over 9}={5b(a+8) \over 9a}={5ab+40b \over 9a}\)

\({4 \over 9}:{x+2y \over y}={4 \over 9}⋅{y \over x+2y}={4y \over 9(x+2y)}={4y \over 9x+18y}\)

\({6a^2-2a+40 \over 2a}={6a^2 \over 2a}-{2a \over 2a}+{40 \over 2a}=3a-1+{20 \over a}\)

\({8a^2-4a-7 \over 2a^2}={8a^2 \over 2a^2}-{4a \over 2a^2}-{7 \over 2a^2}=4-{2 \over a}-{7 \over 2a^2}\)