diketahui PQR, QR//ST. jika panjang ps=12,ST=5 CM, SQ=4 CM dan PT=6cm.hitunglah panjang pr dan qr?

PR / PQ = PT / PS
PR / (PS+SQ) = PT / PS
PR / 16 = 6/4
PR / 16 = 3/2
PR = 3/2 x 16
PR = 24 cm

QR / PR = ST / PT
QR / 24 = 5 / 6
QR = 5/6 x 24
QR = 20 cm