00:03
The given information in this problem is that a equals 6, and the cosine of b is 3 fifths, and we have to make the assumption that angle c is the right angle because the problem doesn't tell us.
00:16
However, that's how we've done it for all the other problems.
00:19
And so i've drawn a sketch, and i've labeled what we know, and our goal is to find the length of b and the length of c.
00:26
So looking at angle b, the cosine would be the adjacent over the hypotenuse, and for what we have, labeled, that would be 6 over c.
00:37
So if we set that equal to 3 over 5, we have a proportion.
00:41
3 over 5 equals 6 over c.
00:43
And we can solve that proportion for c...