In RT triangle ABC, the angle c is equal to 90 degrees, 1, B = 4, C = 7, a 2, B = 16, a: C = 3:5, a, C

In RT triangle ABC, the angle c is equal to 90 degrees, 1, B = 4, C = 7, a 2, B = 16, a: C = 3:5, a, C

(1)
a²+b²=c²
a²+4²=7²
a=√33
(2)
Let a be 3k, then C be 5K
a²+b²=c²
(3k)²+16²=(5k)²
16k²=16²
k=4
a=3*4=12
c=5*4=20