SOLUTION: What is the area of the triangle that has 2 sides of 10cm and and angle of 30 degrees ?

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Question 963999: What is the area of the triangle that has 2 sides of 10cm and and angle of 30 degrees ?

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let the unknown side be X, the height be H.
If 30 is the vertex angle,
sin%2830%2F2%29=%28X%2F2%29%2F10
X=20sin%2815%29
.
.
cos%2830%2F2%29=H%2F10
H=10cos%2815%29
So then the area would be,
A=%281%2F2%29XH
A=10sin%2815%29%2A10cos%2815%29
A=25cm%5E2
.
.
.
If 30 is not the vertex angle,
30%2B30%2BV=180
V=120
A=%281%2F2%29XH
A=10sin%2860%29%2A10cos%2860%29
A=25sqrt%283%29cm%5E2