Answer:
-1
Explanation:
To find the slope of a line, you would need to use the slope formula, and that is

This equation should be used every time you need to find a slope with two given points. If you remember this, you would find questions like this more easy.
First, you would need to plug in your coordinate points into the formula.
You would plug -7 in y2, 2 in y1. And then you will plug in 4 in x2, and -5 in x1.
Your equation should look like this:

Then you solve.
For the top portion of your equation you would get -9. The -5 turns into a positive 5 because when you carry the negative over (distribute it), the negative cancels out and turns into a positive. When you add the 5 and the 4 together, it will get you 9. The bottom portion of the equation will be 9.
Your equation should now look like this:

Now, you divide.
When you divide, the two 9's end up as a whole, and you keep the negative since the negative doesn't cancel out in this situation. When you finish dividing, you would get -1.
Your FINAL answer would be -1.