\({7 \over 5a}+{9 \over 5a}={16 \over 5a}\)

\({7 \over x}-{4 \over 2x}={14 \over 2x}-{4 \over 2x}={10 \over 2x}={5 \over x}\)

\({2 \over 4a}-{9 \over 7b}={14b \over 28ab}-{36a \over 28ab}={14b-36a \over 28ab}={7b-18a \over 14ab}\)

\(6-{3 \over 2p}={6 \over 1}-{3 \over 2p}={12p \over 2p}-{3 \over 2p}={12p-3 \over 2p}\)

\({9x \over y}+{7 \over 5y}={45x \over 5y}+{7 \over 5y}={45x+7 \over 5y}\)

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

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

\({12x \over -27x}=-\frac{4}{9}\)

\({14a \over 2a}=7\)

\({-25ab \over -30ac}={5b \over 6c}\)

\({-18b \over -21ab}={6 \over 7a}\)

\({-15xyz \over 5yz}=-3x\)

\({2ab \over b}+{7ac \over c}=2a+7a=9a\)

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

\({5b \over 7a}-{9a \over 6b}={30b^2 \over 42ab}-{63a^2 \over 42ab}={-63a^2+30b^2 \over 42ab}={-21a^2+10b^2 \over 14ab}\)

\({5 \over a}⋅{7 \over b}={35 \over ab}\)

\({x \over 7}⋅-{4 \over y}=-{4x \over 7y}\)

\({3 \over 4}⋅p={3p \over 4}\)

\({9q \over p}⋅{p+3 \over 6}={9q(p+3) \over 6p}={3q(p+3) \over 2p}={3pq+9q \over 2p}\)

\({4 \over a}:{8 \over b}={4 \over a}⋅{b \over 8}={4b \over 8a}={b \over 2a}\)

\({8 \over 5}:x={8 \over 5}:{x \over 1}={8 \over 5}⋅{1 \over x}={8 \over 5x}\)

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

\({5a \over 9}+{a+1 \over 7}={35a \over 63}+{9(a+1) \over 63}={35a+9(a+1) \over 63}={44a+9 \over 63}\)