a. K = x + x + (x - y) + y + y + (x - y) = 4x
L = (x . x) – (y . y) = x² – y²
b. K = 3z + 2z + y + 3z + y = 2y + 8z
L = (y x 3z) – (z x z) = 3yz – z²
c. K = 3a + 3b + 3a + 3b = 6a + 6b
L = (3a x 3b) – (a x b) – (a x b) – (a x b) = 9ab – 3ab = 6ab
d. K = r + r + r + r + p + p + p + p + p + p + p + p = 4r + 8p
p = sisi yang tegak lurus dengan r
L = (r x r) – 4 x (p x p) = r² – 4p²