The Cross Sections of a Certain Satellite Dish Are Parabolic $d ( x ) = \frac { 14 } { 25 } x ^ { 2 } - \frac { 14 } { 5 } x$

Multiple Choice

The cross sections of a certain satellite dish are parabolic in shape. A cross section through the vertex can be described by the equation $d ( x ) = \frac { 14 } { 25 } x ^ { 2 } - \frac { 14 } { 5 } x$ where d(x) is the depth of the dish (in feet) at a distance of x ft from the edge of the dish. How deep Is the satellite dish?

A) The satellite dish is $6 \frac { 1 } { 4 } \mathrm { ft }$ deep.
B) The satellite dish is $5 \mathrm { ft }$ deep.
C) The satellite dish is $3 \frac { 1 } { 2 } \mathrm { ft }$ deep.
D) The satellite dish is $2 \frac { 4 } { 5 } \mathrm { ft }$ deep.