Find the equation of the hyperbola centered at the origin that has a vertex at (5, 0) and a focus at (9, 0).

Refer to the diagram shown below.

The vertex is at (a,0), with a = 5.
The focus is at (c,0), with c = 9.
Therefore
b² = c² - a²  = 81 - 25 = 56

The equation of the hyperbola is

She should use 12/3 to measure

You can find the area of a rectangle by multiplying the length and height. so multiply 1/2*7/4(which is the simpler version of 1 3/4) and you get 7/8 as your answer.