The verbal expression for 7 to the third power is 343
If it doesn't matter whether the points are integers or not you can just pick a number for either y or x and solve for the other variable. For example, if you pick 3 to be your x, plug it in and then solve for y. Start out with:

Plug in 3 for x:

. Then,

. Subtract 21 from both sides and then divide by -3 on both sides. You end up with y=-7 so one of your points is (3, -7)
I got 11.5 lol I don’t really know why
I'm not 100% sure what this all means because I'm in a different school but, I believe they have a side length of 4600.
P.S. If it doesn't work, I am so sorry