SOLUTION: ABC is a triangle in which SINA:SINB:SINC=7:8:10 and it's perimeter=75cm and m(B)=22 find it's area

Algebra.Com
Question 491873: ABC is a triangle in which SINA:SINB:SINC=7:8:10 and it's perimeter=75cm and m(B)=22 find it's area
Answer by cleomenius(959)   (Show Source): You can put this solution on YOUR website!
The sides are going to be proportional to the opposite sine function. This is the law of sines.
a = 7/25 * 75 = 21 cm
b = 8/25 * 75 = 24 cm
c = 10/25 * 75 = 30 cm
21 cm + 24 cm + 30 cm = 75 cm.
This checks so we have the correct values for the sides.
===========================================================
Now, we must use Herons formula to find our area.
Area ==
s = 21 + 24 + 30 / 2
s = 37.5
Area =
Area =
Area = 240.85 cm.
I am skeptical of the value you gave for the m(B) of 22. This value does not seem to fit with the rest of the data, I do not see where you can have a middle angle of 22 degrees with the sins in those proportions.
Cleomenius

RELATED QUESTIONS

In the right triangle ABC, m (answered by Fombitz)
For any triangle ABC, we have cosA + cosB + cosC =1+4SinA/2SinB/2SinC/2 and SinA/2 +... (answered by robertb)
Which one of the following statements is true for trigonometric functions of two acute... (answered by vleith)
Find the exact value of the following under the given conditions sina=4/5, a lies in... (answered by Alan3354)
In non-right triangle ABC, let A=120 degrees, a = 7cm, and b=3cm. Find side c and angles... (answered by stanbon)
If sinA = 35 and sinB = 513 . Where A and B are acute angles. Find... (answered by Alan3354)
If SinA - SinB = 1/2 and CosA - CosB = 1 Then find Tan(A +... (answered by robertb)
Please can you answer this question A bus travels uniformly from 54 km/h to 72 km/h in (answered by Alan3354)
In triangle ABC a=4 b=11 and c=8 find... (answered by Edwin McCravy)