It's inevitable. At some point in every math class, someone asks the teacher (usually with an exasperated groan), "When are we going to use any of …

# What Is the Area Formula for a Rectangle, a Triangle and a Circle?

Want to know the area of your pizza or the kitchen you're eating it in? Come on, and we'll show you how to figure it out with an area formula. Plus more math concepts.

## More Math Concepts

You might have been in fifth grade the last time you thought about how to multiply fractions. But if you're trying to cut a recipe in half or calculate …

You're sitting in math class trying to survive your latest pop quiz. The questions on Page 1 weren't too hard, but on the second page, you see a …

We all make mistakes. Sometimes, if you play your cards right, they can become valuable learning opportunities. It's called "human error" for a …

Subtracting fractions is simple — almost as simple as multiplying fractions — but the process of subtraction is different depending on whether the …

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Riddle Answer

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