Q. What is the center of the circle x2+y2−19y+26=0? Simplify any fractions. (□,□)
Complete the square for y: To find the center of the circle, we need to complete the square for both x and y. The given equation is x2+y2−19y+26=0. We notice that the x terms are already a perfect square, so we only need to complete the square for the y terms.
Move constant term: First, we move the constant term to the other side of the equation: x2+y2–19y=−26.
Add half of coefficient: Next, we complete the square for the y terms. To do this, we take half of the coefficient of y, which is −219, square it, which is (−219)2=4361, and add it to both sides of the equation.
Simplify the equation: The equation becomes x2+y2−19y+4361=−26+4361. Simplify the right side of the equation by converting −26 to a fraction with the same denominator as 4361, which is −4104. So, the equation is now x2+y2−19y+4361=−4104+4361.
Rewrite y terms: Simplify the right side of the equation: −4104+4361=4257. Now the equation is x2+y2−19y+4361=4257.
Identify center of circle: We can now rewrite the y terms as a perfect square: x2+(y−219)2=4257. This shows that the circle is in the standard form (x−h)2+(y−k)2=r2, where (h,k) is the center of the circle and r is the radius.
Identify center of circle: We can now rewrite the y terms as a perfect square: x2+(y−219)2=4257. This shows that the circle is in the standard form (x−h)2+(y−k)2=r2, where (h,k) is the center of the circle and r is the radius.From the equation x2+(y−219)2=4257, we can see that h=0 and k=219. Therefore, the center of the circle is (0,219).
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