Ab - 0.5b + 1/2 when a = 1 and b = 5

Since you already know the values of a and b, all you have to do is split the problem into little parts and plug everything into its spot. AB would equal 1 (5) which is 5. Athens 0.5b would equal, 0.5 (5) to equal 2.5. So now your equation is 5-2.5+1/2 which equals 3.