So, we know some coordinates of the places:
- Home: (-3, -12)
- School: (-15, 6)
- Grocery: (24, 6)
- Gym: (0, y_gym)
First, we want to determine the line that represents a stree that connects School and Home, that is, the points (-15, 6) and (-3, -12).
Let's represent a line in the standard form:

The slope, "b", can be calculated using the points we know:

Then, we can use the slope-point form and solve for y:

That is the equation of the First Street.
The Main Street passes through Home and Grocery, that is, points (-3 -12) and (24, 6).
Using the same method, we firts get the slope:

And use the slope-point form:

Lastly, we know that Ridge Road is parallel to Main Street and it passes through School. If they are parallel, they have the same slope, so the slope of Ridge Road is:

Since we know School is in thir Road, we can use the slope-point to get the equation for Ridge Road:

And, since we know that the x-coordinate of the Gym is x = 0, we can put this into the equation of the Ridged Road to get its y-coordinate:

The picture we get is the following:
So, the final answers are:
First Street:

Main Street:

Ridge Road:

Coordinates of the Gym:
