Q. What is the center of the circle x2+y2−81=0?Simplify any fractions.(____,____)
Rewrite equation to standard form: We start by rewriting the equation to resemble the standard form of a circle's equation, which is (x−h)2+(y−k)2=r2, where (h,k) is the center of the circle and r is the radius.x2+y2−81=0Add 81 to both sides to isolate the x2 and y2 terms.x2+y2=81
Add 81 to both sides: Now, we compare the equation x2+y2=81 with the standard form of a circle's equation. We notice that the x2 and y2 terms do not have any coefficients or constants added to them, which means that h and k are both 0. Therefore, the center of the circle is at (h,k)=(0,0).
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