Pythagoras’ theorem is a2 + b2 = c2
c is the hypotenuse or slanted line.
Choose either remaining side as a or b
Side A = 3
Side B = 4
3^2 + 4^2 = c2
so
9 + 16 = 25
25 = c2
We want just c so we have to do square root of 25
Which is 5.
So the answer to A, starting object to obstacle 2 is 5m.
The triangle now has the sides of 3, 4 and 5. So a total lap of the course is 12m!