Posted by **Amanda** on Tuesday, April 21, 2009 at 4:30pm.

I have no idea how to do these problems:

Find an equation of each circle.

1. Center (3,5); tangent to the x axis

2. Center (5,-3); tangent to the y axis

3. Tangent to the x axis, y axis, and the line y=5 (two answers)

I just really need help understanding how to do this.

- Circles (Conic Sections) -
**Reiny**, Tuesday, April 21, 2009 at 4:35pm
1. Did you sketch or just visualize the circle?

Isn't the radius 5 ?

so (x-3)^2 + (y-5)^2 = 25

2. Do it the same way.

3. y = 5 is a horizontal line 5 units above the x-axis.

I can visualize a circle in the first quadrant, and another in the second quadrant.

isn't the diameter 5 ?

so isn't the centre 2.5 up from the x-axis and 2.5 to the right of the y-axis?

mmmh?

## Answer This Question

## Related Questions

- Geometry - How to put each circle in standard form? 1. Center of the line 5x-3y...
- math - 1. two circles. x^2+y^2-16x-8y+35=0 and x^2+y^2=5 are given. a. write the...
- calc - standard equations of circles that have centers on line 5x-2y=-21 and are...
- math - a circle is tangent to the y-axis at y=3 and has one x-intercept at x=1 a...
- Math (Equation of a circle) - Find an equation of the circle with its center at...
- GEOMETRY CIRCLES PLEASE - 1.An isosceles triangle with each leg measuring 13 cm ...
- Pre-Calculus - I am having trouble with several problems: 1) Find the ...
- Pre-Calculus - I am having trouble with several problems: 1) Find the ...
- GEOMETRY CIRCLES PLEASE - HELP ME PLEASE. 1.An isosceles triangle with each leg...
- College Algebra - Knowing the given conditions, write the equation of the circle...

More Related Questions