In a circle chords QP and SR intersect externally at A. If AP=7cm,PQ=14cm,AR=8cm then the ratio of AR:RS.
Since QP and SR are chords and they meet at an external point A.
⟹QA.PA=SA.RA
⟹(AP+PQ).AP=AS.AR
AS=21×78=1478cm
AR+RS=1478
RS=1478–8=838
ARRS=8838=6483