A triangle has sides A, B, and C. The angle between sides A and B is (pi)/2. If side C has a length of 4 and the angle between sides B and C is pi/12, what is the length of side A?

1 Answer
Feb 23, 2018

A=1.04"cm"

Explanation:

We have a triangle that looks like this:

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Here, side B is the base leg, side C is the hypotenuse and side A is the vertical leg.

We can say the angle opposite to side A is /_a, and the angle opposite to side C is /_c.

According to the law of sines:

sina/A=sinb/B=sinc/C

Since Side B doesn't matter here, we can say:

sina/A=sinc/C

We need to solve for A. Simply rearrange:

A=(Csina)/sinc

Since a=pi/12, C=4"cm" and c=pi/2, we can input:

A=(4*sin(pi/12))/sin(pi/2)

A=(4*0.259)/1

A=1.04"cm"