Question

A plumber charges 15 per service call, plus 50 per hour.

Answer 1

Answer:

The equation of the cost is C = 50h + 15

Step-by-step explanation:

The form of the linear equation is y = m x + b, where

• m is the slope of the line ⇒ rate of change

• b is the y-intercept ⇒ constant value

∵ A plumber charges 15 per service call

→ That means there is a fixed amount of 15

∵ b is the constant amount

∴ b = 15

∵ It charges 50 per hour

→ That means, the rate of change is 50

∵ m is the rate of change

∴ m = 50

∵ C is the cost for h hours

→ Replace y by C and x by h in the form of the linear equation above

∴ C = m h + b

→ Substitute the values of m and b in the equation

∵ C = 50h + 15

∴ The equation of the cost is C = 50h + 15