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Algebra (all content)

Course: Algebra (all content) > Unit 17

Lesson 3: Standard equation of a circle
Math
Algebra (all content)
Conic sections
Standard equation of a circle
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Features of a circle from its standard equation

CCSS.Math: HSG.GPE.A.1
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Problem

The equation of a circle is given below.
left parenthesis, x, minus, 5, point, 2, right parenthesis, squared, plus, left parenthesis, y, plus, 3, point, 7, right parenthesis, squared, equals, 49
What is its center?
left parenthesis
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
comma
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
right parenthesis
What is its radius?
If necessary, round your answer to two decimal places.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
units
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