Answer:
[tex]\large\boxed{\cos(A)\approx0.08629\to A=85^o}[/tex]
or
[tex]\large\boxed{\cos(A)=0.2}[/tex]
Step-by-step explanation:
[tex]552 = 502 + 352-2(50)(35)\cos(A)\\\\552=854-3500\cos(A)\qquad\text{subtract 854 from both sides}\\\\-302=-3500\cos(A)\qquad\text{divide both sides by (-3500)}\\\\\dfrac{-302}{-3500}=\cos(A)\\\\\cos(A)\approx0.08629\\\\\text{From the table (look at the picture):}\\\\A=85^o[/tex]
If "2" are a square.
[tex]55^2=50^2+35^2-2(50)(35)\cos(A)\\\\3025=2500+1225-3500\cos(A)\\\\3025=3725-3500\cos(A)\qquad\text{subtract 3725 from both sides}\\\\-700=-3500\cos(A)\qquad\text{divide both sides by (-3500)}\\\\\dfrac{-700}{-3500}=\cos(A)\to\cos(A)=\dfrac{1}{5}\to\cos(A)=0.2[/tex]
