A circle in the xy-plane has the equation x2+y2−10x+32y+272=0.Which of the following best describes the location of the center of the circle and the length of its radius?Choose 1 answer:(A) Center: (10,−32)Radius: 417(B) Center: (−10,32)Radius: 417(C) Center: (−5,16)Radius: 3(D) Center: (5,−16)Radius: 3
Q. A circle in the xy-plane has the equation x2+y2−10x+32y+272=0.Which of the following best describes the location of the center of the circle and the length of its radius?Choose 1 answer:(A) Center: (10,−32)Radius: 417(B) Center: (−10,32)Radius: 417(C) Center: (−5,16)Radius: 3(D) Center: (5,−16)Radius: 3
Rewriting the equation: To find the center and radius of the circle, we need to rewrite the equation in standard form, which is (x−h)2+(y−k)2=r2, where (h,k) is the center and r is the radius.
Grouping the terms: First, we group the x terms and the y terms together: (x2−10x)+(y2+32y)=−272.
Completing the square for x terms: Next, we complete the square for the x terms and the y terms. To complete the square, we take half of the coefficient of x (which is −10) and square it, adding and subtracting this value inside the parentheses. We do the same for y with the coefficient of 32.
Completing the square for y terms: For the x terms: x2−10x+(210)2 - 210^2 = x2−10x+25 - 25.For the y terms: y2+32y+(232)2 - 232^2 = y2+32y+256 - 256.
Adding completed squares to both sides: Now we add these completed squares to both sides of the equation: (x2−10x+25)+(y2+32y+256)=−272+25+256.
Simplifying the equation: Simplify the equation: (x−5)2+(y+16)2=9.
Identifying the center and radius: Now we can see that the equation is in standard form, with the center of the circle at (h,k)=(5,−16) and the radius r=9=3.
Correct answer: Comparing with the given options, the correct answer is (D) Center: (5,−16) Radius: 3.
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