One half is 0.50, so compare 0.84 to 0.50. Which is true?
0.84 is greater than 0.50
0.84 equals 0.50
0.84 is less than 0.50.
Answer:
It's simple
Step-by-step explanation:
See what I did there? Simple?
Let 
. The tangent plane to the surface at (0, 0, 8) is
The gradient is
so the tangent plane's equation is
The normal vector to the plane at (0, 0, 8) is the same as the gradient of the surface at this point, (1, 1, 1). We can get all points along the line containing this vector by scaling the vector by 
, then ensure it passes through (0, 0, 8) by translating the line so that it does. Then the line has parametric equation
or 
, 
, and 
.
(See the attached plot; the given surface is orange, (0, 0, 8) is the black point, the tangent plane is blue, and the red line is the normal at this point)
Positive square root of 0.25 = 0.5
Hope this helps. - M
<span>You did not include the equations that you want to assess whether they can be used to solve for the radius (r).
Likely, the equation of the circumference, C = 2*Pi*r is included, if so => r = C / (2*Pi).
If you round Pi to 3.14, the equation may be written r = C / 6.28.</span>
