The red line is 40" The black dot is 90* The green dot is 20* What is the length of the blue line? What is the lenght of the yellow line?

sin(20*) = 40"/x or x = 40"/sin(20*) 116.95 If I remember correctly. * Edit I'm stupid * That is for the yellow side. -- I didn't read the whole thing thought you were just asking for one side.

If you have a right triangle and you know the length of 2 sides you can find the missing side by using pythagorean theorem...A squared + B squared = C squared. If you know two sides you can find the missing angles by using trigonometry...Sine, Cosine, and Tangent. Sine = Opposite/Hypotenuse......Cosine = Adjacent/Hypotenuse......Tangent = Opposite/Adjacent If you know one of the angles (other than the right 90*) and one of the sides, then you use these functions to find the missing sides. In the example given... To find the length of the Blue line you use Tangent of 20* (green dot)... Set up the equation -->Tan 20* = 40" (red Line) / x (blue line)... swap x & tan 20*.... you get --> x = 40" / Tan 20* ...(tan 20* = 0.36397)...which equals 109.899" To find the length of the yellow line you use Sine of 20* ... Set up the equation --> Sin 20* = 40" / x .... swap x & sin 20.... you get x = 40" / sin 20* ...(sin 20 = 0.34202)...which equals 116.952176". Should be clear as mud now.... Sorry it is so long.

Blue = Y Yellow = H TAN 20 = 40/Y; Y = 40/(TAN 20) = 109.9 SIN 20 = 40/H; H = 40/(SIN 20) = 117 (116.95) Check: X^2 + Y^2 = H^2; 40^2 + 109.9^2 = 13677.8 116.95^2 = 13677.3 Close enough. Drawing is deceiving. What math homework problem did we just solve?

Now that I look at the drawing again it is drawn a little wacky for the dimensions that I gave. It is for something that I'm building. Thanks eveyone for the replies!