We are trying to figure out the third measurement
Point P (-2,4) and Point Q(-4,-3)
So I believe that we are supposed to multiply the numbers in the curved lines( idk how to spell , -2 times 4 is -8 and -4 times -3 is 12. We then use the formula a^ + b^ = c^.
The equation is -8^ + 12^ = c^
-8 to the second power is -64, 12 to the second power is 144. We then add those two numbers and get c^ = 80^
80 to the second power is 640, and thats your answer
I don't know if its correct, but I tried my best, and I hope it will at least help a bit