100 POINTS HEELP PLSSS!!!

See below.

Step-by-step explanation:

1.

y = 100 + 65x

y = 40 + 80x

100 + 65x = 40 + 80x

-15x = -60

x = 4

y = 100 + 65x = 100 + 260 = 360

(4, 360)

2.

The lines intersect at the point (4, 360).

At the point of intersection, where x = 4, it shows that by doing 4 hours of labor, both shops cost the same.

3.

Mike's:

y = 100 + 65x = 100 + 65(3) = 100 + 195 = 295

Amy's:

y = 40 + 80x = 40 + 80(3) = 40 + 240 = 280

For 3 hours of labor, Amy's shop is cheaper at $280. Mike's costs $295.