math
posted by donovan .
A childrens play area is triangular. The sides of the play area measure 90m ,225m and 255m respectively . Calculate the area of the play area?

Use Law of Cosines to find one of the
sides:
a = 90 m.
b = 225 m.
c = 255 m.
CosB = (a^2+c^2b^2)/2ac
CosB=(8100+6502550625) / 45900=0.4902
B = 60.6 Deg.
Area = 0.5ac*sinB
Area = 0.5*90*255*sin60.6 = 10,000 m^2. 
Correction: Used Law of cosines to find
one of the angles. 
thanx