Thread: Find an equation of the largest sphere with center...

Originally Posted by thomann061

Find an equation of the largest sphere with center (11, 19 , 12) that is contained completely in the first octant.

Need help solving... thank you!

The coordinates give you the answer.

yes i know, i am confused about how to find the radius.

Originally Posted by thomann061

yes i know, i am confused about how to find the radius.

Have you plotted the center on a graph? If the radius is 19, is it possible for it not to exceed the 1st octant? What about 12?

yes i have graphed it. i came up with this as an answer so far: (x-11)^2 + (y-19)^2 + (z-12)^2 = 0. i dont know what you mean by if the radius is 19? i thought it would be around 2 or 4.

Originally Posted by thomann061

yes i have graphed it. i came up with this as an answer so far: (x-11)^2 + (y-19)^2 + (z-12)^2 = 0. i dont know what you mean by if the radius is 19? i thought it would be around 2 or 4.

You think a radius of 2 or 4 is the largest sphere you can fit in the first octant?

Also, your equation is of a point.

as you can tell i am very confused... i just can't seem to understand how to solve this or think about it visually. could you show me how to solve for it?

Originally Posted by thomann061

as you can tell i am very confused... i just can't seem to understand how to solve this or think about it visually. could you show me how to solve for it?

Draw a picture a find the center.

i found the center, i still cant tell how to find the radius

Originally Posted by thomann061

i found the center, i still cant tell how to find the radius

If you found the center, how far can you move away from it before you hit an axis: x, y, or z?

i mean 12 from the y axis

Originally Posted by thomann061

i mean 12 from the y axis

So if you move 12 units, you won't cross the x-axis?

ha i mean 19 from the x axis

Originally Posted by thomann061

ha i mean 19 from the x axis

Here is a sphere of 8 and 19. You tell me.

ohhhh okay its 11^2 for the radius