To measure the area of a given shape, a general rule of thumb is to multiply the length by the width and use square units to express the resulting value. Measure the area of any shape or space with instructions from a college-level math teacher in this free video on geometry.
So, how do you measure area? Hi. I'm Jimmy Chang. I've been teaching college mathematics for nine years. And, when it comes to measuring area, you have to think about a couple of things. Number one, when you're measuring area, you're measuring two dimensions, which means that you are often measuring two dimensional figures. And so, one rough definition of area is the amount of space occupied in a two dimensional figure. Now, because you are measuring only two dimensions at a time, your answer should always be in square units, like square feet, square inches, square miles. So in terms of notation, this is what you would have. For example, square feet. You have feet followed by a square, or feet squared. Or, if it's square inches, you put inches first, then square. But that gives the reader an idea that is how area is measured. It's always going to be in square units. Now, here's a couple of basic formulas to kind of help you out. For example, suppose you want to find the area of a rectangle. Let's just say it was 8 feet by 6 feet. Now, oftentimes people only multiply the numbers, but it's always better to ensure that, when you use square units, to multiply 8 feet times 6 feet together. So, in other words, you're going to have 8 feet times 6 feet, since the area of a rectangle is length times width. So, you'll have as a result, 8 times 6 is 48, but feet times feet is feet squared. So, the area of this rectangle is 48 square feet. As long as you incorporate the units as you're multiplying, you'll never go wrong. Now, another formula is that of a triangle. The area of a triangle is one half base times height. Now, let's just say the base was 6 feet and the height was 4 feet. Plugging everything back in, you'll have one half the base is 6 feet times the height, which is 4 feet. Half of 6 is 3 feet times 4 feet, which is equal to 12 square feet. So, I'm Jimmy Chang and there are a couple of examples as to how you measure area.