Kennedy, defining the variables just means telling what your variable represents.
Let's look at the first company. If you drove 150 miles, how much would it cost? You'd be charged $40 plus 6 cents for each mile.
.06 x 150 = 9.00, so your total charge would be $49.
How do we write an equation representing that? If we say that m = the number of miles and T = our total charge (defining our variables), then our charge for miles is .06 x m, written .06m. We need to add the $40.
If you were to write this, you'd probably say 40 + .06m = T. In math, though, you want your answer on the left, then anything with variables, so our equation is T = .06m + 40.
Can you do the second one yourself?
