\({7 \over 4x}+{9 \over 4x}={16 \over 4x}={4 \over x}\)

\({3 \over a}+{5 \over 2a}={6 \over 2a}+{5 \over 2a}={11 \over 2a}\)

\({9 \over 5x}+{4 \over 2y}={18y \over 10xy}+{20x \over 10xy}={18y+20x \over 10xy}={9y+10x \over 5xy}\)

\(4+{2 \over 7a}={4 \over 1}+{2 \over 7a}={28a \over 7a}+{2 \over 7a}={28a+2 \over 7a}\)

\({9p \over q}+{6 \over 4q}={36p \over 4q}+{6 \over 4q}={36p+6 \over 4q}={18p+3 \over 2q}\)

\({2a \over a}={2 \over 1}=2\)

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

\({8x \over 14x}=\frac{4}{7}\)

\({18p \over 3p}=6\)

\({25xy \over -40xz}=-{5y \over 8z}\)

\({-10b \over -14ab}={5 \over 7a}\)

\({18abc \over -2bc}=-9a\)

\({5xy \over y}+{4xz \over z}=5x+4x=9x\)

\(3a-{9 \over 7a}={3a \over 1}⋅{7a \over 7a}-{9 \over 7a}={21a^2 \over 7a}-{9 \over 7a}={21a^2-9 \over 7a}\)

\({6b \over 3a}-{9a \over 8b}={48b^2 \over 24ab}-{27a^2 \over 24ab}={-27a^2+48b^2 \over 24ab}={-9a^2+16b^2 \over 8ab}\)

\({8 \over x}⋅-{9 \over y}=-{72 \over xy}\)

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

\({3 \over 2}⋅p={3p \over 2}\)

\({2y \over x}⋅{x+8 \over 5}={2y(x+8) \over 5x}={2xy+16y \over 5x}\)

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

\(-{9 \over 4}:p=-{9 \over 4}:{p \over 1}=-{9 \over 4}⋅{1 \over p}=-{9 \over 4p}\)

\({7 \over 3}:{a-4b \over b}={7 \over 3}⋅{b \over a-4b}={7b \over 3(a-4b)}={7b \over 3a-12b}\)

\({2x \over 3}+{x-8 \over 4}={8x \over 12}+{3(x-8) \over 12}={8x+3(x-8) \over 12}={11x-24 \over 12}\)

\({-7a+4 \over 3a+5}-8={-7a+4 \over 3a+5}-{8(3a+5) \over 3a+5}={-7a+4-8(3a+5) \over 3a+5}={-7a+4-24a-40 \over 3a+5}={-31a-36 \over 3a+5}\)

\({4p^2-5p-2 \over 7p^2}={4p^2 \over 7p^2}-{5p \over 7p^2}-{2 \over 7p^2}=\frac{4}{7}-{5 \over 7p}-{2 \over 7p^2}\)