I personally use y2-y1 over x2-x1 because it's simple. Plot two y values and two x values. The first ones you plotted are x1 and y1, the others are x2 y2. Now subtract y2-y1 and x2-x1. Afterwards, divide the y value by the x value, that will give you slope.
The second one would be the answer. You want to plug in for this question. You can divide over the five leaving you with (x-2)^2 =25. Since you are squaring this answer, you want to get either 5 or negative five. Both -3 and 7 will do that.
Simple...
you have:

You want to find m-->>>
1.)Isolate m

Leaving you with...
F*

=

Keep isolating m-->>>


Square root to solve what just m is-->>>

=

That is how you solve for m...
Thus, your answer.
117 divided by g is 19.5
I hope this helps.