First find how much the point moved in y to the second point.
8-0=8
So one side is 8.
Then find how much it moved in x. 7-(-8)=15
So the other side is 15
This will give you 2 sides of a triangle where one sides lenght is 8 the other is 15. Use the pythagoras theorem which is x squared plus y squared = c squared
8^2+15^2=c^2
64+225=c^2
289=c^2 Take the square root of both sides to solve for C
