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McGraw Hill Integrated II, 2012

MH

McGraw Hill Integrated II, 2012 View details

Study Guide and Review

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Exercise 37 Page 795

Substitute the center point and the radius into the standard equation of a circle.

x^2+y^2=34^2

Practice makes perfect

Let's begin by recalling the standard equation of a circle. In this equation ( h, k) represents the center of a circle and r is the radius. (x- h)^2+(y- k)^2= r^2In our exercise we are asked to write the equation of Kat's safety circle. Since her reach is 19 inches and the hatchet handle is 15 inches, the radius of the circle will be the sum of these values. r= 19+ 15=34 The radius of Kat's safety circle is 34 inches. We also know that the center of Kat's safety circle is the origin. Therefore, to write the equation we should substitute 34 for the radius and ( 0, 0) for the center point into the standard equation.

(x- h)^2+(y- k)^2= r^2

SubstituteValues

Substitute values

(x- 0)^2+(y- 0)^2= 34^2

Subtract terms

x^2+y^2=34^2

Subchapter links

1 Circles and Circumference p.792

2 Measuring Angles and Arcs p.792

3 Arcs and Chords p.793

4 Inscribed Angles p.793

5 Tangents p.794

6 Secants, Tangents, and Angle Measures p.794

7 Special Segments in a Circle p.795

8 Equations of Circles p.795

9 Areas of Circles and Sectors p.796