Answer:
CD = 10√3
Step-by-step explanation:
First of all, you need to understand the terms. The <em>incenter</em> is the center of an inscribed circle. Such a circle is tangent to all three sides of the triangle at points B, D, and F. The distances BG, DG, and FG are each the radius of the circle.
The diagram shows FG = 22, so that is also the measure of DG. This gives you two of the three sides of right triangle CDG, so you know enough to apply the Pythagorean theorem.
CG^2 = CD^2 + DG^2
28^2 = CD^2 + 22^2
300 = CD^2 . . . . . . . . subtract 22^2
10√3 = CD . . . . . . . . . take the positive square root
The measure of CD is 10√3.
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The process is to understand the geometric relationships and what they mean regarding the algebraic relationships. Then you use the algebraic relationships to write equations that let you find the unknowns you seek.
