+0

# Geometry Problem

0
151
3
+74

In the circle below, AB is parallel to CD, AD is a diameter of the circle, and AD = 36.What is the length of AB? Express your answer in terms of pi.

Jun 23, 2018

### 3+0 Answers

#1
+94545
+1

Since  AD  is a diameter, then ABD will form a right triangle with angle ABD  = 90°

So...angle ADB   = 40°

And we can find AB  as :

sin (40)  = AB  / 36

AB  = 36 * sin (40)  = 23.140353948732  ≈   7.3658 pi  units

Jun 24, 2018
#2
+1

Here is another method:
If we designate O as the center of the circle, then:
Line AO = BO =radius of the circle = 18
ABO is an isosceles triangle with angles =50, 50, 80
18/sin(50) =AB/sin(80), and:
AB =23.14035 =7.3658pi

Jun 24, 2018
#3
0

It sure is 7.3658 pi units!

Jun 24, 2018

### New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.