Select the correct answer.

Which equation represents a circle with center [tex]$Z(-3,5)$[/tex] and a radius of 4 units?

A. [tex]$(x-3)^2+(y+5)^2=4$[/tex]
B. [tex][tex]$(x-3)^2+(y+5)^2=16$[/tex][/tex]
C. [tex]$(x+3)^2+(y-5)^2=4$[/tex]
D. [tex]$(x+3)^2+(y-5)^2=16$[/tex]



Answer :

To determine the equation that represents a circle with a center at [tex]\( Z(-3, 5) \)[/tex] and a radius of 4 units, we use the standard form of the equation of a circle:

[tex]\[ (x - h)^2 + (y - k)^2 = r^2 \][/tex]

where [tex]\( (h, k) \)[/tex] is the center of the circle and [tex]\( r \)[/tex] is the radius.

Given in the problem:
- The center [tex]\( (h, k) \)[/tex] = [tex]\((-3, 5)\)[/tex]
- The radius [tex]\( r \)[/tex] = 4 units

We substitute [tex]\( h = -3 \)[/tex], [tex]\( k = 5 \)[/tex], and [tex]\( r = 4 \)[/tex] into the standard form equation:

[tex]\[ (x - (-3))^2 + (y - 5)^2 = 4^2 \][/tex]

Simplify the equation:

[tex]\[ (x + 3)^2 + (y - 5)^2 = 16 \][/tex]

Hence, the equation that represents the circle is:

[tex]\[ (x + 3)^2 + (y - 5)^2 = 16 \][/tex]

Now we match this with the provided choices:

A. [tex]\((x-3)^2+(y+5)^2=4\)[/tex]
B. [tex]\((x-3)^2+(y+5)^2=16\)[/tex]
C. [tex]\((x+3)^2+(y-5)^2=4\)[/tex]
D. [tex]\((x+3)^2+(y-5)^2=16\)[/tex]

The correct answer is:

D. [tex]\((x+3)^2+(y-5)^2=16\)[/tex]