00:01
Given this information about a triangle, note that any triangle is labeled with capital letters for angles and sides that are lowercase for side lanes.
00:09
So here i'm given two sides and an angle between the sides.
00:16
What am i trying to solve for? i'm trying to solve for my missing sidelines c.
00:20
Okay, so given side angle side, how can i find that missing side length? well, in this case, when i'm given side angle side, i can either do, i can only do in this case.
00:35
Law of cosines, right? because for law of signs, if i were solving for a side, i would need at least two angles.
00:42
If i'm solving for an angle, i need at least one angle.
00:44
So i'm going to do law of cosines.
00:46
My side squared equals the other two sides squared minus two, multiply those sides together, times cosine.
00:55
And what is this angle here? it has to be the angle across from c, which will be 72.
01:02
And since everything is on my right side, i could just plug this all into the calculator...
