Skip to main content
Ch. 2 - Functions and Graphs
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514당신이 사용하는 게 아니라요?교과서 변경
3장, 문제 60

Complete the square and write the equation in standard form. Then give the center and radius of each circle and graph the equation. x² + y² - 6y -7=0

검증된 단계별 안내
1
Start with the given equation: \(x^{2} + y^{2} - 6y - 7 = 0\).
Group the \(y\) terms together and isolate the constant on the other side: \(x^{2} + (y^{2} - 6y) = 7\).
Complete the square for the \(y\) terms. Take half of the coefficient of \(y\), which is \(-6\), divide by 2 to get \(-3\), then square it to get \(9\). Add \(9\) to both sides to keep the equation balanced: \(x^{2} + (y^{2} - 6y + 9) = 7 + 9\).
Rewrite the perfect square trinomial as a binomial squared: \(x^{2} + (y - 3)^{2} = 16\).
Identify the center and radius of the circle from the standard form \((x - h)^{2} + (y - k)^{2} = r^{2}\). Here, the center is \((0, 3)\) and the radius is \(\sqrt{16}\).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
5m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Completing the Square

Completing the square is a method used to rewrite quadratic expressions in the form (x - h)² or (y - k)² by adding and subtracting a constant. This technique helps transform the equation of a circle into its standard form, making it easier to identify key features like the center and radius.
추천 영상:
06:24
Solving Quadratic Equations by Completing the Square

Standard Form of a Circle

The standard form of a circle's equation is (x - h)² + (y - k)² = r², where (h, k) is the center and r is the radius. Writing the equation in this form allows direct identification of the circle's center coordinates and radius, which are essential for graphing.
추천 영상:
5:18
Circles in Standard Form

Graphing Circles

Graphing a circle involves plotting its center (h, k) on the coordinate plane and using the radius r to mark points equidistant from the center. Understanding how to interpret the standard form equation enables accurate sketching of the circle's shape and position.
추천 영상:
5:18
Circles in Standard Form