Question

The circle below is centered at the origin and has a radius of 8. What is itsequation?yO A. x²-√2²=8B. x² + y² = 8C. x² - y² = 64D. x² + y² = 64-1010-10810

Answer 1

Answer: The standard form of the circle equation is:

$\begin{gathered} (x-h)^2+(y-k)^2=r^2\rightarrow(1) \\ \\ \\ \\ (h,k)=(x,y)\rightarrow\text{ Center of the circle} \end{gathered}$

According to the equation (1) we can have the following answer:

$\begin{gathered} r=\text{ 8}\rightarrow r^2=8^2=64 \\ \\ (h,k)=(x,y)=(0,0)\text{ }\rightarrow\text{ Center} \\ \\ \therefore\rightarrow \\ \\ (x)^2+(y)^2=64\text{ }\rightarrow\text{ Option\lparen A\rparen} \end{gathered}$