How Do You Find the Area of a Circle if You Know the Radius?

How Do You Find the Area of a Circle if You Know the Radius?

Note:

If you know the radius of a circle, you can use it to find the area of that circle. Just plug that value into the formula for the area of a circle and solve. Watch this tutorial to see how it's done!

Keywords:

  • area
  • circle
  • area of a circle
  • radius
  • solve for area
  • use radius

Background Tutorials

  • Evaluating Expressions

      • How Do You Evaluate an Algebraic Expression?How Do You Evaluate an Algebraic Expression?

      How Do You Evaluate an Algebraic Expression?

      Plugging variables into an expression is essential for solving many algebra problems. See how to plug in variable values by watching this tutorial.

      • What is a Variable?What is a Variable?

      What is a Variable?

      You can't do algebra without working with variables, but variables can be confusing. If you've ever wondered what variables are, then this tutorial is for you!

      • What's the Order of Operations?What's the Order of Operations?

      What's the Order of Operations?

      Check out this tutorial where you'll see exactly what order you need to follow when you simplify expressions. You'll also see what happens when you don't follow these rules, and you'll find out why order of operations is so important!

  • Areas of Circles and Sectors

      • What is the Formula for the Area of a Circle?What is the Formula for the Area of a Circle?

      What is the Formula for the Area of a Circle?

      Did you know that you can figure out the formula for the area of a circle by first turning the circle into a parallelogram? It seems a little weird, but it really works! Watch this tutorial to see how it's done!

Further Exploration