Jackie is a toll booth employee. one day, she wrote the expression: 0.75m= 15.75she let m represent the number of motorcycles that crossed the bridge that day

21

Step-by-step explanation:

The expression Jackie came up with is:

0.75m = 15.75.

To get the value of m, we divide both sides by 0.75

0.75m = 15.75.

0.75m/0.75 = 15.75/0.75

m = 1575/75

     = 21

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb