1st use formula c^2=a^2 + b^2 - 2ab CosC to find length c
2nd once you know all 3 sides a,b,c then use formula
A=Square root of [ s (s-a) * (s-b)* (s-c) ]
where s = (a+b+c)/2
for 1st question. c = 20.18, s =25.09, area = 14.92 square unit.
you do the 2nd question