Question

Select the correct answer.Circle F is represented by the equation (x+6)2 + (y+ 8)2 = 9. What is the length of the radius of circle F?OA. 3OB. 9OC.10O D. 81

Answer 1

SOLUTION

$(x+6)^2+(y+8)^2=9$

Recall that the equation of circle is given as;

$\begin{gathered} (x-a)^2+(y-b)^2=r^2 \\ where \\ (a,b)\text{ is the centre} \\ r\text{ is the radius.} \end{gathered}$

Considering our question;

$\begin{gathered} (x-(-6))^2+(y-(-8))^2=3^2 \\ \Rightarrow r=3 \end{gathered}$

The radius of the circle is 3 units