Question

Find the equation of the circle with center at (0, 0) and diameter of 18.

Answer 1

Answer:

${x}^{2} + {y}^{2} = 81$

Step-by-step explanation:

The general for for the equation of a circle is

${(x - a)}^{2} + {(y - b)}^{2} = {r}^{2}$

Where a is the x coordinate of the centre, b is the y coordinate of the centre and r is the radius.

In your case, a=0, b=0, r=9

Substituting these values into the general form gives the answer.