2a + b - c2a + b - c = 2*8 + 12 - 18 = 16 + 12 - 18 = 10
(a + b) c(a + b) c = (8 + 12) 18 = 20 18 = 360
a^2 - b^2 + ca^2 - b^2 + c = 8^2 - 12^2 + 18 = 64 - 144 + 18 = -62
2a + b - c
2a + b - c = 2*8 + 12 - 18 = 16 + 12 - 18 = 10
(a + b) c
(a + b) c = (8 + 12) 18 = 20 18 = 360
a^2 - b^2 + c
a^2 - b^2 + c = 8^2 - 12^2 + 18 = 64 - 144 + 18 = -62