How do you determine the number of possible triangles and find the measure of the three angles given #AB=14, BC=21, mangleC=75#?

1 Answer
Nov 1, 2017

No Triangle

Explanation:

Since the given information is for a SSA triangle it is the ambiguous case. In the ambiguous case we first find the height by using the formula #h=bsin A#.

Note that A is the given angle and its side is always a so the other side will be b .

So if #A < 90^@# and if

  1. #h < a < b# then then there are two solutions or two triangles.

  2. #h < b < a# then there is one solution or one triangle.

  3. #a < h < b# then there is no solution or no triangle.

If #A >=90^@# and if

  1. #a > b# then there is one solution or one triangle.

  2. #a <=b# there is no solution

#h=21 sin75^@~~20.28#, since #14 < 20.28 < 21# we have

#a< h < b# so we have no solution or no triangle.