Question

in triangle ABC, AB=90 in., BC=80 in., and angle B measures 50 degrees. What is the approximate perimeter of the triangle?

Answer 1

A. 242.4

Explanation:

edge 2020

Answer 2

we know that

the Law of Cosines established:
AC² = AB² + BC² - 2·AB·BC·cos(b)
Therefore
AC = √(90² + 80² - 2·90·80·cos(50)
=√5243.86
= 72.4 in

Now you can sum up all the sides in order to find the perimeter:
AB + BC + AC = 90 + 80 + 72.4 = 242.4 in

the answer is
242.4 in