How to find the area of a triangle

Here is how you find the area of a triangle. Well it's a little bit harder then a square so you'll have to listen closely. Just pretend you have a rectangle( or a parallelogram) that is 9 for the height, and 4 for the base. Then if you split it in half, it will become a triangle. But then the triangle and the rectangle( or parallelogram) will be the same area even though they are not the same area. So for finding the area of a triangle, you will multiply the two sides together, and split it in half. If the two sides of the triangle are 9 and 4, the answer would be 36, but you have to divide it by two, so the answer is 18cm squared.