\({3 \over 9 x} + {4 \over 9 x} = {7 \over 9 x}\)

\({9 \over a} + {7 \over 8 a} = {72 \over 8 a} + {7 \over 8 a} = {79 \over 8 a}\)

\({7 \over 8 a} + {6 \over 2 b} = {7 b \over 8 a b} + {24 a \over 8 a b} = {7 b + 24 a \over 8 a b}\)

\(3 + {9 \over 8 x} = {3 \over 1} + {9 \over 8 x} = {24 x \over 8 x} + {9 \over 8 x} = {24 x + 9 \over 8 x}\)

\(7 p + {5 \over 6 p} = {7 p \over 1} ⋅ {6 p \over 6 p} + {5 \over 6 p} = {42 p^{2} \over 6 p} + {5 \over 6 p} = {42 p^{2} + 5 \over 6 p}\)

\({4 a \over b} - {9 \over 2 b} = {8 a \over 2 b} - {9 \over 2 b} = {8 a - 9 \over 2 b}\)

\({4 b \over 8 a} + {2 a \over 9 b} = {36 b^{2} \over 72 a b} + {16 a^{2} \over 72 a b} = {16 a^{2} + 36 b^{2} \over 72 a b} = {4 a^{2} + 9 b^{2} \over 18 a b}\)

\({7 x \over x} = {7 \over 1} = 7\)

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

\({-10 p \over -14 p} = \frac{5}{7}\)

\({-35 x \over -5 x} = 7\)

\({6 a b \over -27 a c} = -{2 b \over 9 c}\)

\({-6 y \over 9 x y} = -{2 \over 3 x}\)

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

\({2 a b \over b} - {4 a c \over c} = 2 a - 4 a = -2 a\)

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

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

\(-{9 \over 7} ⋅ x = -{9 x \over 7}\)

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

\(-{9 \over 7} : p = -{9 \over 7} : {p \over 1} = -{9 \over 7} ⋅ {1 \over p} = -{9 \over 7 p}\)

\({4 p \over 9} + {p - 8 \over 5} = {20 p \over 45} + {9 (p - 8) \over 45} = {20 p + 9 (p - 8) \over 45} = {29 p - 72 \over 45}\)

\({-9 a - 6 \over 4 a + 5} - 3 = {-9 a - 6 \over 4 a + 5} - {3 (4 a + 5) \over 4 a + 5} = {-9 a - 6 - 3 (4 a + 5) \over 4 a + 5} = {-9 a - 6 - 12 a - 15 \over 4 a + 5} = {-21 a - 21 \over 4 a + 5}\)

\({4 x^{2} + 6 x + 20 \over 2 x} = {4 x^{2} \over 2 x} + {6 x \over 2 x} + {20 \over 2 x} = 2 x + 3 + {10 \over x}\)

\({9 p^{2} - 5 p + 2 \over 6 p^{2}} = {9 p^{2} \over 6 p^{2}} - {5 p \over 6 p^{2}} + {2 \over 6 p^{2}} = 1\frac{1}{2} - {5 \over 6 p} + {1 \over 3 p^{2}}\)