Find the value of side b, the value of angle A,  and the value of angle B.

This image has been Flagged as inappropriate Click to unflag
Image (1 of 1)

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The length of side b can be calculated in two ways:

1. Using the Pythagorean theorem


2. Noting that this triangle is a multiple of a 3-4-5 right triangle where the legs are 3 and 4 and the hypotenuse is 5. For this right triangle, the legs are 3x5=15 and 4x5=20 and the hypotenuse is 5x5=25.

Angle A can be determined using any of the trigonometric functions. If we apply the sine function to determine the measure of angle A, we get:

`sin A=20/25=0.8`


The sum of the two oblique angles of a right triangle is 90 degrees, therefore:


Therefore b=15, A=53.13 degrees and B=36.87 degrees.

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Approved by eNotes Editorial Team