Mohon dibantu soal matematika ini

01.
6/(6 + 3) = x/(x + 4)
6/9 = x/(x + 4)
6(x + 4) = 9x
6x + 24 = 9x
24 = 3x
8 = x

6/(6 + 3) = y/12
6/9 = y/12
y = 12 × 6/9
y = 8

x + y = 8 + 8 = 16

02.
s² = r² + t²
s² = 5² + 12²
s² = 25 + 144
s² = 169
s = √169
s = 13

luas selimut = πrs
= π × 5 × 13
= 65π cm²

luas permukaan ½ bola = ½ × 4πr²
= 2πr²
= 2 × π × 5²
= 2 × π × 25
= 50π cm²

luas bangun = 65π + 50π = 115π cm²