<u>Answer:</u>
The standard form of the equation of the circle is
<u>Solution:</u>
Given, a circle has center (-8, 9) and x – axis as tangent.
First, let's determine r.
The center is 9 above the x-axis and the circle is tangent to the x-axis, so the radius r should be equal to 9.
The center moved 8 to the left, so substitute x by (x + 8).
The center moved 9 up, so substitute y by (y − 9).
You can determine these numbers by filling in the center coordinates, the outcome must be zero. [x+8=−8+8=0]
The standard equation
So, the equation becomes
Hence, standard form of the circle is