In a circle radius rcm, a chord 16(sqrt{3}cm) long is 10cmfrom the centre of the circle. Find, correct to the nearest cm, the value of r
-
A.
22cm -
B.
17cm -
C.
16cm -
D.
15cm
Correct Answer: Option B
Explanation
In the diagram
|AM| = |MB| – (frac{|AB|}{2})
= (frac{16sqrt{3}}{2})cm
= 8(sqrt{3})cm
in (Delta) AMO, r2 = |AM|Z + |MO|2
r2 = (8(sqrt{3}))2
+ 102
= 64 x 3 + 100
= 192 + 100
= 292
r = (sqrt{292})
17.088cm
17cm