PQR is a triangle in which PQ = 10cm and QPR = 60oS is a point equidistant from P and Q. Also S is a point equidistant from PQ and PR. If U is the foot of the perpendicular from S on PR, find the length SU in cm to one decimal place

A.

2.7

B.

4.33

C.

3.1

D.

3.3

Correct answer is B

\(\bigtriangleup\)PUS is right angled

\(\frac{US}{5}\) = sin60o

US = 5 x \(\frac{\sqrt{3}}{2}\)

= 2.5\(\sqrt{3}\)

= 4.33cm