How To Find The Volume Of A Triangular Prism

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How To Find The Volume Of A Triangular Prism

Working out the volume of a triangular prism is made simple and straight-forward when presented by a teacher in this three minute videojug clip.

Let's say we want to work out the area of the following prism. As we can see it's a triangular prism. A triangular prism has three important dimensions that we need to be concerned with.

First of all we have our height, lets say it's four centimeters and this is from the lowest point of the shape to the highest point. We also have the width, or the base, of the triangle, on the base shape. Lastly we have the length of the prism.

lets say that is 5 centimeters for our example. To find the volume of this prism what we first have to do is work out the area of the base shape, here. To do that we need to remember that the area of a triangle is the following: A half base times height.

That's what the 'b' and the 'h' stand for. So for our triangle we are going to have one half multiplied by two, multiplied by four. two multiplied by four is eight and half of this is four.

Remember our units are centimeters squared, because we are dealing with an area and that's in two dimensions. So lets remember that the area of this triangle here is four centimeters squared. I'll write it up here.

Now the final step to work out the volume of the prism is to multiply this area by the length. So the volume is equal to five multiplied by four which is twenty and we're dealing with centimeters cubed because now, we are dealing with a volume which is a 3D measurement. Also a good way to remember is that here, with five, we are dealing with centimeters, multiplied by centimeters squared, with the four, centimeters multiplied by centimeters squared, it's quite logical to see that it's centimeters cubed.

And here we have our volume.
Just to recap: first of all you work out the area of the base shape. You then multiply this area by the length of the prism.

Remembering your units are centimeters cubed this gives us the volume of the prism.
And, that's how you work out the volume of a triangular prism.