As an alternative you can use the "3­4­5" method of creating a right angle. For any triangle with sides that are 3, 4, and 5 units long, the corner formed by the intersection of the 3-unit and 4-unit sides will be a right triangle. This holds true for triangles that are multiples of these numbers such as 6­8­10 or 9­12­15. Once the base line and the 90-degree tangent have been established, you can plot the remaining points. Measure along the x axis to determine the width of the unit. It is possible to establish another 90-degree angle for this line, but it is much easier to simply measure twice, once toward the top and once at the bottom, and connect the dots. Measure along your base line 12-0, and mark the beginning and ending points. Then use two tape mea- sures, one to measure up 9-0, and the other to trian- gulate the 15-0 between the 9-0 mark on the tape, and the 12-0 mark on the floor. That will establish a right angle. This technique is easiest to do with three people--one to hold the end of each tape measure on its respective mark, and the third to move the tapes back and forth until the 12-0 and the 15-0 marks are aligned with one another. Make sure that you are con- sistent about which side of the tape measure you are using. Drawing a line through this point and the origi- nal corner mark will establish a line perpendicular to the base line. The same method may be used to establish the top line of the unit. The remaining points are plotted according to their measurements from a known position by following the dimensions shown on the sketch. Often it is helpful to think of the layout as a graph with an x and a y axis, and the layout of the remaining points is a process of measuring from these axes. The widths of the two leg bottoms can be measured directly from either side of the portal. The remainder of the points that establish the diagonal lines can be plotted up from the bottom and over from one of the sides. The lines between the points can be drawn in with a straightedge, or if the distance is too great, use a chalk line. Whatever the method, it is best to finish by darkening in the line with a Sharpie so that it will be easy to see and less likely to be accidentally swept away. 368 IllustratedTheatreProductionGuide2ed