Assuming all four sides are the same pitch, you know that the two "long" sides will touch at the ridgeline, and that the ridgeline will be a foot long (the difference between the lengths of the two sides.) So the two "short" sides will be triangles with an 18' base, and the two "long" sides will be trapezoids with a 19' base and a 1' top. All will have the same height, and that's the only thing you still need to draw them (you don't actually need any angles.)
The height of each panel is the hypotenuse of a triangle that has sides of 4' (the height of the center of the roof) and 9' (half the length of the short side of the roof.) You can use the Pythagorean Theorem to calculate the hypotenuse of that triangle: the square root of (4 x 4 + 9 x 9). The result is approximately 9' 10-3/16"
If you don't want all the sides to have the same pitch, but you do want them to come to a point, then you need four triangles: two are 19' at the base and that value up there high, and the other two are 18' at the base and sqrt(4 x 4 + 9.5 x 9.5) high - 10' 3-11/16". Again, no angles needed.
