Area of a Circle with Radius 5
A circle of radius 5 has area 25π square units.
Problem
Answer
Step-by-step solution
Step 1: Write the formula
Area of a circle is πr².
Step 2: Substitute
r = 5, so r² = 25.
Why this works
Radius is half the diameter. If a problem gives diameter 10, convert to r = 5 before using πr². Circumference uses 2πr and is a different quantity.
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A two-step linear equation: move the constant, then divide. The check is 3(7) − 7 = 14.
Frequently asked questions
Should the answer be a decimal?
Only if the assignment asks for an approximation. Exact form 25π is preferred in most algebra and geometry courses.