Question

The TV repairman charges $40 to come out to your house and check the TV

plus $25 per hour of labor. Write an equation to find the cost of repairing a TV.

Answer 1

The equation to find the cost of repairing a TV is:

y = 25x + 40

Explanation:

We know that the slope-intercept form of the line equation is

`y=mx+b`

where m is the slope or rate of change and b is the y-intercept

Given that the TV chairman charges $40 to come out to your house and check the TV plus $25 per hour of labor.

It means $40 is the y-intercept because it represents the starting point/condition of the repairman.

Let 'x' be the number of hours and y be the cost.

The rate of change = 25$ per hour of labor

• The rate of change can also be termed as the slope.

Thus, m = 25

Hence, the slope-intercept form of the line equation becomes

y = mx+b

substituting m = 25 and b=40

y = 25x + 40

Therefore, the equation to find the cost of repairing a TV is:

y = 25x + 40

Validation:

y = 25x + 40

putting x = 1 to determine the cost if labor works for 1 hour.

y = 25(1) + 40 = $65

putting x = 2 to determine the cost if labor works for 2 hours.

y = 25(2) + 40 = $95