Things You'll Need:
- scientific calculator or trig table
-
Step 1
As our example, let's take a triangle with side lengths 6 and 11 with an angle of 70 degrees between. The first step is to multiply 6 and 11 and then divide the product by 2.
(6)(11) = 66, and 66/2 = 33. -
Step 2
The next step is to use a calculator or trig table to figure the sine of 70 degrees. There are three main trigonometric functions, sine, cosine, and tangent. Sine(70) is .9396.
Now multiply .9396 times the number you computed in step 1. (.9396)(33) = 31.0068. So the area of the triangle is essentially 31 square units -
Step 3
For a triangle with side lengths of A and B and an angle of x degrees between them, the formula for the area of the triangle is (1/2)ABsin(x).









Comments
derbyka said
on 6/23/2009 That's cool! I never knew you could do it that way!