Math help, I don't understand

Question

Find the standard form of the equation of a circle with the center (-3,4) and tangent to the x-axis 

Answer 1

Hello,  Allie

 

Listen, if you plot the point and draw a circle with a center on (-3,4) will help you understand this problem better.  The radius for this circle is going to be 4.  Why? Because the vertical distance from point (-3,4) is 4 units from the x-axis.  As you might recall, Allie, the standard form of a circle is

 

(x-h)^2+(y-k)^2=r^2, where (h,k) is the center of the circle and r is the radius.  So, substituting, we get

[x-(-3)]^2+[y-4]^2=4^2

(x+3)^2+(y-4)^2=4^2     This should be the equation of the line.

 

Don't forget to rate my answer.  :) Bye..

D. Y. Taylor