What is the equation of the circle tangent to the x-axis and with center (3, 5)?

  • Context: MHB 
  • Thread starter Thread starter mathdad
  • Start date Start date
  • Tags Tags
    Circle
Click For Summary
SUMMARY

The equation of the circle tangent to the x-axis with center at (3, 5) is derived using the standard circle equation, which is \((x-h)^2+(y-k)^2=r^2\). Given that the radius \(r\) is equal to the y-coordinate of the center, \(k=5\), the radius squared is \(r^2=25\). Substituting \(h=3\) and \(k=5\) into the equation results in \((x-3)^2+(y-5)^2=25\). This equation represents the desired circle.

PREREQUISITES
  • Understanding of the standard equation of a circle
  • Knowledge of Cartesian coordinates
  • Basic algebraic manipulation skills
  • Familiarity with the concept of tangency in geometry
NEXT STEPS
  • Explore the properties of circles in coordinate geometry
  • Learn about the relationship between radius and tangency
  • Study the derivation of conic sections equations
  • Investigate applications of circles in real-world problems
USEFUL FOR

Students, educators, and anyone interested in geometry, particularly those studying conic sections and their properties.

mathdad
Messages
1,280
Reaction score
0
Find the equation of the circle tangent to the x-axis and with center (3, 5).

Can someone provide the steps needed to solve this problem?
 
Mathematics news on Phys.org
The equation of a circle centered ar $(h,k)$ is given by:

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

If the circle is tangent to the $x$-axis, then its radius must be $r=|k|\implies r^2=k^2$, thus we have:

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

We are given $(h,k)=(3,5)$, so plug in those numbers. :D
 
MarkFL said:
The equation of a circle centered ar $(h,k)$ is given by:

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

If the circle is tangent to the $x$-axis, then its radius must be $r=|k|\implies r^2=k^2$, thus we have:

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

We are given $(h,k)=(3,5)$, so plug in those numbers. :D

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

(x - 3)^2 + (y - 5)^2 = 5^2

(x - 3)^2 + (y - 5)^2 = 25
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 59 ·
2
Replies
59
Views
67K
  • · Replies 2 ·
Replies
2
Views
1K
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
5
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K