Tolong di jawab pakai cara

Teorema Pythagoras
c^2 = a^2 + b^2

1.
8^2 = y^2 + y^2
64 = 2y^2
32 = y^2
4V2 = y

2.
20^2 = (3y)^2 + (4y)^2
400 = 9y^2 + 16y^2
400 = 25y^2
16 = y^2
y = 4