Question

if 2(a/k)+1=9 what does a/k equal?

Answer 1

Just say that a/k equals some other variable x, and substitute:
2x + 1 = 9
2x + 1 - 1 = 9-1
2x = 8
2x ÷ 2 = 8÷2
x = 4
a/k = 4