Discover Area Of A Triangle Cuemath

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Here’s a triangle whose base is b and height is h. We have to find the area of this triangle.

area of a triangle

The Normal Way
Most eighth graders will be able to tell you that the area of a triangle is 1/2 x b x h. So, for example, if b is 8 cm and h is 6 cm, then the area of the triangle will be 1/2 x 8 x 6 = 24 cm^2. Teachers do teach kids this formula and how to apply it, but they don’t teach kids why this formula works? Was it pulled out of a hat? Did someone just dream it up? Of course not, but kids are never given the full story! And unfortunately, they don’t even ask for it – asking is something which is not encouraged!

The Cuemath Way
Cuemath takes a very different approach, believing in the principle that kids need to know the why behind the what. Here’s the same triangle. Now, we do a simple but very interesting thing – we complete the rectangle formed using the triangle’s base and height.

area of a triangle

It’s easy to see that the left part of the triangle has an area half that of the left part of the rectangle, while the right part of the triangle has an area half that of the right part of the rectangle. Thus, the total area of the triangle is half the total area of the rectangle. But – what’s the total area of the rectangle? b x h of course – that’s something we learn very early on. The triangle’s area is therefore 1/2 x b x h.