\({6 \over 7x}+{3 \over 7x}={9 \over 7x}\)

\({4 \over x}-{3 \over 8x}={32 \over 8x}-{3 \over 8x}={29 \over 8x}\)

\({9 \over 4p}+{3 \over 8q}={18q \over 8pq}+{3p \over 8pq}={18q+3p \over 8pq}\)

\(9+{5 \over 2a}={9 \over 1}+{5 \over 2a}={18a \over 2a}+{5 \over 2a}={18a+5 \over 2a}\)

\({6a \over b}+{5 \over 7b}={42a \over 7b}+{5 \over 7b}={42a+5 \over 7b}\)

\({4a \over a}={4 \over 1}=4\)

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

\({-15x \over 21x}=-\frac{5}{7}\)

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

\({20pq \over 36pr}={5q \over 9r}\)

\({14b \over -16ab}=-{7 \over 8a}\)

\({6xyz \over -2yz}=-3x\)

\({7pq \over q}+{5pr \over r}=7p+5p=12p\)

\(5x+{7 \over 9x}={5x \over 1}⋅{9x \over 9x}+{7 \over 9x}={45x^2 \over 9x}+{7 \over 9x}={45x^2+7 \over 9x}\)

\({6q \over 9p}-{4p \over 7q}={42q^2 \over 63pq}-{36p^2 \over 63pq}={-36p^2+42q^2 \over 63pq}={-12p^2+14q^2 \over 21pq}\)

\({2 \over a}⋅-{3 \over b}=-{6 \over ab}\)

\({x \over 6}⋅-{2 \over y}=-{2x \over 6y}=-{x \over 3y}\)

\(-{9 \over 7}⋅a=-{9a \over 7}\)

\({8b \over a}⋅{a+4 \over 6}={8b(a+4) \over 6a}={4b(a+4) \over 3a}={4ab+16b \over 3a}\)

\({5 \over a}:{2 \over b}={5 \over a}⋅{b \over 2}={5b \over 2a}\)

\(-{8 \over 3}:x=-{8 \over 3}:{x \over 1}=-{8 \over 3}⋅{1 \over x}=-{8 \over 3x}\)

\({7 \over 9}:{x+4y \over y}={7 \over 9}⋅{y \over x+4y}={7y \over 9(x+4y)}={7y \over 9x+36y}\)

\({3p \over 4}+{p-8 \over 5}={15p \over 20}+{4(p-8) \over 20}={15p+4(p-8) \over 20}={19p-32 \over 20}\)

\({x^2-7x+8 \over 6x^2}={x^2 \over 6x^2}-{7x \over 6x^2}+{8 \over 6x^2}=\frac{1}{6}-{7 \over 6x}+{4 \over 3x^2}\)