SOLUTION: In ABC, A=45 degrees, b=15 cm and c=22 cm. Find the area of the triangle.

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Question 1121733: In ABC, A=45 degrees, b=15 cm and c=22 cm. Find the area of the triangle.
Found 2 solutions by Boreal, ikleyn:
Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
Find a by Law of Cosines:
a^2=b^2+c^2-2bc cos A
a^2=225+484-2(330) cos 45
=709-660(0.7071)=709-466.69=242.31
sqrt(242.31)=15.6 (rounded)
length of all 3 sides combined is 52.6 and half of it, 26.3, is s
sqrt(s*(s-a)(s-b)(s-c))=sqrt(26.3*11.3*4.3*10.7)=sqrt (13673.71)
=116.9 cm^2 (Hero's Formula)

Answer by ikleyn(52797)   (Show Source): You can put this solution on YOUR website!
.

You can solve it in much more easy way.


In this problem, two side lengths of the triangle are given and the angle concluded between these two sides.


Then the area of the triangle is equal to 


    A =  =  = 116.67 cm^2.

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On formulas for the area of a triangle see the lesson
    - Formulas for area of a triangle,
in this site.


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