Question

a first class letter in 2013 costs $.46 for the first once and $0.20 for every additional once. ,The cost is c=.046 +.20(z-1), where z is the letter in ounces, solve for z.

Answer 1

The cost is c=.46 +.20(z-1)

Solve for z

To solve for z, first we remove the parenthesis

c= .46 + .20z - .20

combine like terms

c= 0.26 + 0.20z

Now we need to get z alone

Subtract 0.26 on both sides

c - 0.26 = 0.20z

Now divide both sides by 0.20

`(c-0.26)/(0.20)=z`

We got z alone

`z=(c-0.26)/(0.20)`