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

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The equation of the circle tangent to the x-axis with center at (3, 5) can be derived using the standard circle formula. The radius of the circle is equal to the y-coordinate of the center, which is 5, hence r = 5. Substituting the center coordinates into the equation results in (x - 3)² + (y - 5)² = 5². This simplifies to (x - 3)² + (y - 5)² = 25. Therefore, the final equation of the circle is (x - 3)² + (y - 5)² = 25.
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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?
 
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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
 
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