9-4 law of cosines

angle C=60 degrees
side b=5
side a=8

c^2=5^2+8^2-2*5*8*cos60                                        
c=7

sin 60/7=sin A/8
8sin60=7sinA
A=sin^-1(8sin60/7)
angle A=81.787

180-60-81.787=38.213

First you have to know the formula for law of cosine. The formula is leg^2=adj. leg^2+other adj. leg^2-2*adj. leg*other leg*cos(angle between). Then you plug what you are given into to formula I just gave you to find one of the sides.  When you plug all that in you get that side c is 7.  Now you have to find the rest of the angles.  You can use law of sines like I did, or you can use law of cosine again.  I used law of sin and made a proportion thing.  I put the measure of angle C over side c equal to sin A over the measure of side a which is 8.  You have to take the inverse of sin because you are finding an angle now.  Angle A is 81.787, now you have to find the last angle of the triangle.  All you have to do now is subtract 180 from all the angles  you have to get 38.213.