7. An electrician charges according to the equation C = 75n + 60, where C represents the total charge, in dollars, for a house call, and n represents the time, in hours that the job takes. Identify the slope and the C-intercept and explain what each one means.
How much money would a 2 h house call cost?
How many hours did the job take if the total charge was $435?

435555

Step-by-step explanation:

331

B. 40 meters

Step-by-step explanation:

— Estimating

The rectangle enclosing the path has sides of length 9 m and 14 m, so its perimeter is 2(9+14) = 46 m. The distance covered will be shorter than that.

The distance from A to C is longer than the distance from D to C, so we know the distance will be longer than 2·14+9 = 37 m.

Only one answer choice fits in the range 37 < d < 46.

— Detailed calculation

The distance from B to C is the hypotenuse of a right triangle with sides 9 and 12. You will recognize that these side lengths are 3 times the side lengths of a 3-4-5 right triangle, so the hypotenuse distance is 3·5 = 15 meters.

The circuit length is ...

AB +BC +CD +DA = 2 + 15 + 14 + 9 = 40 . . . . meters