Answer:
[tex]C(h)=\$30+xh[/tex]
Step-by-step explanation:
Let
C-----> the cost of having a plumber spend h hours at your house
h----> the number of hours
x----> the cost per hour of labor
we know that
The linear equation that represent the cost C is equal to
[tex]C(h)=\$30+xh[/tex]
In this linear equation in the slope-intercept form (y=mx+b)
the slope is equal to [tex]m=x\frac{\$}{hour}[/tex]
the y-intercept b is equal to [tex]b=\$30[/tex] ---> charge for coming to the house
