Question

In triangle ABC, BC=4 centimeters, m angle B=m angle c, and m angle a = 20 degrees. What is AC to two decimal places?

Answer 1

Answer:

The correct answer AC = 11.52

Step-by-step explanation:

From the figure attached with this answer shows the triangle ABC.

BC=4 centimeters, m angle B=m angle c, and m angle a = 20 degrees

To find AC

From the figure we can see that D is the mid point and AD⊥BC

Then BD = CD = 4/2 = 2 cm

<BAD = 10° and <CAD = 10°

By using trigonometric ratio,

sin 10 = CD/AC = 2/AC

AC = 2/sin 10 = 2/0.1736 = 11.52

Therefore the value of AC = 11.52 cm