I can't see your diagram, but I assume it is a triangle, with two sides of 80 and the longest side being from the home to the school. Set it up like this:
80^2 + 80^2 = c^2 where the ^ symbol means an exponent
1600 + 1600 = c^2
3200 = c^2 now root both sides
The distance is 56.5. No, it is not the same as from the shop to the park.