\({8 \over 4a}+{9 \over 4a}={17 \over 4a}\)

\({8 \over a}+{4 \over 9a}={72 \over 9a}+{4 \over 9a}={76 \over 9a}\)

\({7 \over 5x}-{4 \over 3y}={21y \over 15xy}-{20x \over 15xy}={21y-20x \over 15xy}\)

\(5+{3 \over 8p}={5 \over 1}+{3 \over 8p}={40p \over 8p}+{3 \over 8p}={40p+3 \over 8p}\)

\(2x+{3 \over 5x}={2x \over 1}⋅{5x \over 5x}+{3 \over 5x}={10x^2 \over 5x}+{3 \over 5x}={10x^2+3 \over 5x}\)

\({6x \over y}+{3 \over 5y}={30x \over 5y}+{3 \over 5y}={30x+3 \over 5y}\)

\({7q \over 5p}+{4p \over 3q}={21q^2 \over 15pq}+{20p^2 \over 15pq}={20p^2+21q^2 \over 15pq}\)

\({9a \over a}={9 \over 1}=9\)

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

\({25x \over -30x}=-\frac{5}{6}\)

\({24p \over 4p}=6\)

\({-15ab \over -20ac}={3b \over 4c}\)

\({12y \over -16xy}=-{3 \over 4x}\)

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

\({5xy \over y}-{7xz \over z}=5x-7x=-2x\)

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

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

\(-{7 \over 3}⋅x=-{7x \over 3}\)

\({9 \over a}:{7 \over b}={9 \over a}⋅{b \over 7}={9b \over 7a}\)

\(-{7 \over 6}:p=-{7 \over 6}:{p \over 1}=-{7 \over 6}⋅{1 \over p}=-{7 \over 6p}\)