Step-by-step explanation:
but ... you had already correctly answered the first part.
L² + W² = d²
Pythagoras ...
all you needed to do now was do the calculations. no "brainware" needed ...
30² + 10² = d²
900 + 100 = d²
1000 = d²
d = 31.6227766... ≈ 31.6 units
