00:01
Okay, in this scenario, we got two different triangles that we are trying to find missing parts for.
00:06
We're in use law of cosines.
00:08
I'm using going to use two different versions because this version is going to help me find the sideline, which is going to be for part one.
00:14
This will help me find a missing angle, which is going to be for part two.
00:18
So for part one, a is what we're trying to solve for.
00:21
So i'm going to set this up with a squared is equal to b squared, which is going to be 11 squared, plus 9 squared, minus two, times b, times c, times the cosine of 46.
00:36
Okay, so that means a squared is equal to 121 plus 81 minus.
00:46
Let's here, we've got two, it's here, two times 11 times nine, that'll be 22 times nine, gives me 198 cosine of 46.
01:01
From here, i can put the 121 ,81 again, so i do that.
01:06
That's going to be 202 minus 198 times the cosine of 46.
01:12
And then to get the a value, we will do square root here.
01:16
So i'll just plug this in my calculator as is.
01:19
And i get 8.
01:20
Let's go 03 for a.
01:25
Okay.
01:26
So from there, if i have the a value, then i can go to law of signs.
01:30
So i'll do that to help you find angle b here.
01:33
So law of science tells me i can.
01:35
Can do, let me scroll down a little bit here.
01:38
I can do the sign of b divided by 11 is equal to the sign of 46 divided by my 8 .03.
01:50
So we can multiply both sides by 11.
01:52
So i get the sign of b is equal to 11 times the sign of 46 divided by 8 .03.
02:05
And then we can take the inverse sign here.
02:07
So inverse sign, so that b will equal to the inverse sign of 11 times the sign of 46 divided by 8 .03.
02:19
And that is going to come out to 80 point, let's just go with 20 degrees...