November 10, 2008

This resource has been contributed by Winpossible, and can also be accessed on their website by clicking here -
Area of a Triangle.

In this mini- lesson, you'll learn the formulas used for calculating area of triangles. It will be shared with the help of some examples and practice questions with solution, using video explanations by the instructor.

Then you'll practice with some important formulas to calculate the area of triangles. If the base of a triangle is b and the height is h, then the area of the triangle is: ½ × base × height. E.g. if base of a triangle is 20 cm and height 10 cm, then calculated area using above formula is ½ × 20 × 10 = 100 cm^{2}.

If base of the triangle and its area is known, then height is given by: height = 2 × Area/Base. E.g. if the area of a triangle is 300 cm^{2} and height is 10 cm, then base is 60 cm.

If three sides of a triangle a, b, c are given, we can use Heron’s formula:

Area =?((s)(s - a)(s - b)(s - c) where s= (a+b+c)/2

Given the lengths of two sides of a triangle a, b and the measure of angle*C* between them, the following formula can be used: Area of triangle = 1/2 ab sin *C*.

In this mini- lesson, you'll learn the formulas used for calculating area of triangles. It will be shared with the help of some examples and practice questions with solution, using video explanations by the instructor.

Then you'll practice with some important formulas to calculate the area of triangles. If the base of a triangle is b and the height is h, then the area of the triangle is: ½ × base × height. E.g. if base of a triangle is 20 cm and height 10 cm, then calculated area using above formula is ½ × 20 × 10 = 100 cm

If base of the triangle and its area is known, then height is given by: height = 2 × Area/Base. E.g. if the area of a triangle is 300 cm

If three sides of a triangle a, b, c are given, we can use Heron’s formula:

Area =?((s)(s - a)(s - b)(s - c) where s= (a+b+c)/2

Given the lengths of two sides of a triangle a, b and the measure of angle

This FREE mini-lesson is a part of Winpossible's online course that covers all topics within Geometry. Click on the video below to go through it. If you like it, you can buy our online course in Geometry by clicking here.

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