Respuesta :

we know that

the equation of the sphere is equal to

[tex](x-h)^{2} +(y-k)^{2}+(z-l)^{2}=r^{2}[/tex]

where

(h,k,l) is the center of the sphere

r is the radius of the sphere

Step 1

Find the center of the sphere (h,k,l)

Let

A(8,7,6)  B(9,9,9)

we know that

the midpoint of the diameter is the center point

Find the midpoint AB

in the x-coordinate

=(8+9)/2------> 8.5

in the y-coordinate

=(7+9)/2------> 8

in the z-coordinate

=(6+9)/2------> 7.5

the center is (8.5,8,7.5)

Step 2

Find the length of the diameter (distance AB)

A(8,7,6)  B(9,9,9)

[tex]d=\sqrt{(x-x1)^{2}+(y-y1)^{2}+(z-z1)^{2}}[/tex]

[tex]dAB=\sqrt{(9-8)^{2}+(9-7)^{2}+(9-6)^{2}}[/tex]

[tex]dAB=\sqrt{(1)^{2}+(2)^{2}+(3)^{2}}[/tex]

[tex]dAB=\sqrt{14}\ units[/tex]

the diameter is [tex]\sqrt{14}\ units[/tex]

the radius is [tex]r=(\sqrt{14} )/2\ units[/tex]

Step 3

Find the equation of the sphere

[tex](x-h)^{2} +(y-k)^{2}+(z-l)^{2}=r^{2}[/tex]

[tex]r=(\sqrt{14} )/2\ units[/tex]

the center is (8.5,8,7.5)

Substitute

[tex](x-8.5)^{2} +(y-8)^{2}+(z-7.5)^{2}=(\sqrt{14} )/2)^{2}[/tex]

[tex](x-8.5)^{2} +(y-8)^{2}+(z-7.5)^{2}=(14/4)[/tex]

[tex](x-8.5)^{2} +(y-8)^{2}+(z-7.5)^{2}=(3.5)[/tex]

therefore

the answer is

The equation of the sphere is

[tex](x-8.5)^{2} +(y-8)^{2}+(z-7.5)^{2}=(3.5)[/tex]

we are given

diameters has endpoints (8,7,6) and (9,9,9)

Center:

we will find mid point of these two points

[tex](a,b,c)=(\frac{8+9}{2},\frac{7+9}{2},\frac{6+9}{2})[/tex]

[tex](a,b,c)=(8.5,8,7.5)[/tex]

Radius:

radius is half of distance between these two points

[tex]d=\sqrt{(9-8)^2+(9-7)^2+(9-6)^2}[/tex]

[tex]d=\sqrt{14}[/tex]

now, we can find radius

[tex]r=\frac{d}{2}[/tex]

[tex]r=\frac{\sqrt{14}}{2}[/tex]

Equation of sphere:

we can use formula

[tex](x-a)^2+(y-b)^2+(z-c)^2=r^2[/tex]

now, we can plug values

and we get

[tex](x-8.5)^2+(y-8)^2+(z-7.5)^2=(\frac{\sqrt{14}}{2})^2[/tex]

[tex](x-8.5)^2+(y-8)^2+(z-7.5)^2=\frac{14}{4}[/tex].............Answer