Question

A water company charges $20 for service and $2.75 for every thousand gallons of water used in month. Construct a linear model to represent the water bill; how much would you be charged if you used 14-thousand gallons of water this month?

Answer 1

`\$58.50`

Explanation:

Let

x -----> thousand. gallons of water used in month

y ----> the total charge in dollars

we know that

The linear equation in slope intercept form is equal to

`y=mx+b`

where

m is the rate or slope

b is the y-intercept or initial value

In this problem we have that

`m=\$2.75\ per\ thousand.\ gallons`

`b=\$20`

substitute

The linear equation that represent this situation is

`y=2.75x+20`

so

If you used 14-thousand. gallons of water this month

then

x=14

substitute the value of x in the linear equation and solve for y

`y=2.75(14)+20`

`y=\$58.50`