berdasarkan gambar berikut , nilai x + y =

x² = 15² - 9²
x² = 225 - 81
x² = 144
x = √144
x = 12 cm

y² = 15² + 8²
y² = 225 + 64
y² = 289
y = √289
y = 17

nilai x + y = 12 + 17 = 29 (D.)