Question

what is the radius of a circle whose equation is ((x + 5)^2 + (y - 3)^2 = 4^2)?

○ 2 units
○ 4 units
○ 8 units
○ 16 units

Explanation:

Step1: Recall circle standard form

The standard equation of a circle is $(x-h)^2 + (y-k)^2 = r^2$, where $r$ is the radius.

Step2: Compare with given equation

Given equation: $(x+5)^2 + (y-3)^2 = 4^2$. Here, $r^2 = 4^2$, so $r=4$.

Answer:

B. 4 units