Question

What is the radius of a circle whose equation is (x + 5)2 + (y – 3)2 = 42? 2 units 4 units 8 units 16 units

Answer 1

Answer:

Option B.

Step-by-step explanation:

The given equation is

$(x+5)^2+(y-3)^2=4^2$       ...(1)

The standard form of a circle is

$(x-h)^2+(y-k)^2=r^2$      ...(2)

where, (h,k) is center and r is radius of the circle.

On comparing (1) and (2) we get

$h=-5,k=3,r=4$

It means center of the circle is (-5,3) and radius of the circle is 4 units.

Therefore, the correct option is B.