Building a Skateboard Ramp
Date: 9/19/95 at 10:24:6 From: Anonymous Subject: Skateboard ramp I'm trying to build a skateboard ramp, a pyramid with a flat top, a height of one foot, angle of ascent thirty degrees, other angles ninety degrees and sixty degrees. If the height is one foot, what are the measurements of the other two sides of the triangle (the base and the slope) ? - Thanks
Date: 9/25/95 at 16:35:36 From: Doctor Andrew Subject: Re: Skateboard ramp FIGURE: A RIGHT TRIANGLE /| / | z/ | / |x / | / a | -------- y (a is an angle: 30, 60, etc) Here are a couple of facts about this triangle that should help: * z^2 = x^2 + y^2. (The Pythagorean Theorem) (so z = sqrt(x^2 + y^2)) * y = x / tan(a) (tangent is a trigonometry function. You can just use it on your calculators. To make life easier, tan 30 = 1/(sqrt(3)), tan 60 = sqrt(3),tan(45)=1) So, if a is a 30 degree angle: y = 1 ft / tan(30) = 1 / (1/sqrt(3)) = sqrt(3) which is about 1.732 ft. and if a is a 60 degree angle y = 1 ft/ (tan(30)) = 1 / sqrt(3) = 1 /(1.732) = .577350 ft Good luck! -Doctor Andrew, The Geometry Forum
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