Category Archive for: ‘Geometry’

Finding the Directrix of a Parabola, Given its Vertex and Focus

Finding the directrix of a parabola, given its vertex and focus, when the equation of the parabola and its orientation are unknown.

Determining the Orientation of the Parabola Any time we are given only one or more of the following: Focus Vertex Axis of Symmetry Directrix and are asked to find one or more of the others, we must first determine the orientation of the parabola, if we are not already told what it is (as we usually are not). In the …

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How to Find the Area of an Equilateral Triangle Given its Height

Calculating the area of a triangle is easy so long as you have a right triangle. But what if you don’t? This tutorial walks through a solution when we are given the side length of an equilateral triangle and asked to find the area of the triangle.

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