Question

a - b + 3c , para a = 1,b = 3 e c = 5

Answer 1

a - b + 3c     a = 1 b = 3 e c = 5
1-3 + 3.5
1 - 3 + 15= 13

Answer 2

a = 1 b = 3 c = 5
1 - 3 + 3.5
-2 + 15 = 13 Somente substituir!!