Answer:
RN = 6.25
Explanation:
Triangle Proportionality Theorem: If a line parallel to one side of a triangle intersects the other two sides, then it divides the two sides proportionally.
Therefore,
MQ : MP = MR : MN
⇒ 8 : (8 + 5) = 10 : (10 + RN)
⇒ 8 : 13 = 10 : (10 + RN)
⇒
Cross multiply and solve:
⇒ 8(10 + RN) = 10 × 13
⇒ 80 + 8RN = 130
⇒ 8RN = 130 - 80
⇒ 8RN = 50
⇒ RN = 50 ÷ 8
⇒ RN = 6.25