Question

question 8 of 10
what is the equation of the circle with center (-3.2, 2.1) and radius 4.3?
a. (x + 3.2)^2+(y - 2.1)^2 = 4.3^2
b. (x - 2.1)^2-(y + 3.2)^2=(4.3)^2
c. (x + 2.1)^2+(y - 3.2)^2 = 4.3^2
d. (x - 3.2)^2+(y + 2.1)^2=(4.3)^2

Explanation:

Step1: Recall circle - equation formula

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

Step2: Identify values of $h$, $k$, and $r$

Given center $(-3.2,2.1)$ and radius $4.3$, so $h=-3.2$, $k = 2.1$, and $r = 4.3$.

Step3: Substitute values into formula

Substitute $h=-3.2$ and $k = 2.1$ into $(x - h)^2+(y - k)^2=r^2$, we get $(x-(-3.2))^2+(y - 2.1)^2=4.3^2$, which simplifies to $(x + 3.2)^2+(y - 2.1)^2=4.3^2$.

Answer:

A. $(x + 3.2)^2+(y - 2.1)^2=4.3^2$