Question

find the area of a circle with a diameter of 4: either enter an exact answer in terms of π or use 3.14 for π and enter your answer as a decimal. units²

Explanation:

Step1: Find the radius

The diameter of the circle is given as 4. The radius \( r \) of a circle is half of its diameter, so \( r=\frac{d}{2}=\frac{4}{2} = 2 \).

Step2: Calculate the area

The formula for the area \( A \) of a circle is \( A=\pi r^{2} \). Substituting \( r = 2 \) into the formula, we get \( A=\pi\times(2)^{2}=\pi\times4 = 4\pi \). If we use \( 3.14 \) for \( \pi \), then \( A = 3.14\times4=12.56 \).

Answer:

If in terms of \( \pi \), the area is \( 4\pi \) square units. If using \( 3.14 \) for \( \pi \), the area is \( 12.56 \) square units. (You can choose either based on the requirement. If we consider the exact answer in terms of \( \pi \), the answer is \( 4\pi \); if decimal, \( 12.56 \))