\(-9 x ⋅ 2 = -18 x\)

\(3 x ⋅ 5 y = 15 x y\)

\(-6 a ⋅ -2 b = 12 a b\)

\(-7 p ⋅ -4 p = 28 p^{2}\)

\(5 a ⋅ -3 b ⋅ 4 c = -60 a b c\)

\(3 a ⋅ 2 b ⋅ -a = -6 a^{2} b\)

\(7 x + 5 x = 12 x\)

\(4 p q + p q = 5 p q\)

\(9 x + 8 x + 3 x = 20 x\)

Kan niet korter.

Kan niet korter.

\(0 ⋅ -2 a = 0\)

\(6 x ⋅ -5 x y = -30 x^{2} y\)

\(-3 y ⋅ -1 ⋅ -4 x y = -12 x y^{2}\)

\(a + a + a + a + a + a + a = 7 a\)

\(6 x - 8 x = -2 x\)

\(-7 a - 3 a = -10 a\)

\(-2 x y - 4 x y = -6 x y\)

\(3 a + 0 = 3 a\)

\(-8 p + 8 p = 0\)

\(7 x - 8 y + 9 x = 16 x - 8 y\)

\(-6 a + 4 b + 2 b = -6 a + 6 b\)

\(-p - 9 q - 2 p + 6 q = -3 p - 3 q\)

\(3 a + 9 + 2 a - 4 = 5 a + 5\)

\(4 x + -6 y - 2 x = 2 x - 6 y\)

\(-6 a - -4 a - 5 b = -2 a - 5 b\)

\(-9 p - p q - 8 q + 2 p q = -9 p - 8 q + p q\)

\(-x y - 2 y - 5 x y + 2 y = -6 x y\)