You can put this solution on YOUR website! Slope is change in y divided by change in x. You may do it in either direction so long as you are consistent.
The y values here are -3 and 4. The difference is -3-4=-7.
The x values here are -2 and 5. The difference is -2-5=-7
The slope is -7/-7 = 1
Done the other way, 4- (-3)/5-(-2) = 7/7 or 1.