Kelas : VIII Materi : Lingkaran Tolong jawab no 21 beserta cara, terimakasih.

RA : RB = 5 : 2

misal
RA = 5x
RB = 2x

PQ² = AB² - (RA - RB)²
28² = 35² - (5x - 2x)²
784 = 1.225 - (3x)²
9x² = 1.225 - 784
9x² = 441
x² = 441 / 9
x² = 49
x = √49
x = 7

maka RA = 5x = 5 . 7 = 35 cm

jawaban D