How to Calculate Radius (r) in Geometry Equations

Learn how to accurately calculate the radius in geometry equations, including the circular equation for r.

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To calculate for r in a formula, identify its relationship with other variables. For instance, in the equation of a circle (x - h)² + (y - k)² = r², solve for r by finding the square root of both sides after isolating r²: r = sqrt((x - h)² + (y - k)²). This process adapts based on the specific equation used.

FAQs & Answers

  1. What is the formula to find the radius of a circle? The formula to find the radius (r) of a circle is r = sqrt((x - h)² + (y - k)²), derived from the equation of a circle.
  2. How do I isolate r in an equation? To isolate r, manipulate the equation to remove other variables and solve for r by taking the square root if r is squared.
  3. Can the radius be calculated from diameter? Yes, the radius can be calculated from the diameter by dividing the diameter by 2.

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For further learning about geometry and mathematical concepts, check our videos on angles, equations, and shape properties to deepen your understanding!

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