Answer:
Step-by-step explanation:
A Descent rate,
B 10725ft,
C 25min
11/12 as a fraction is 11/12; as a decimal it is ~ 0.9167
Let
x-------> the first number
y------> the second number
we know that


equation 

equation 
substitute equation 1 in equation 2

using a graph tool-----> to resolve the second order equation
see the attached figure
the solution is

(1) The value of x is 25
(2) The measure of ∠CBD is 60°
Explanation:
(1) The given two angles are vertical angles. Since, vertical angles are equal, we can add the two angles to determine the value of x.
Thus, we have,

Subtracting 5x from both sides, we have
Adding 10 to both sides , we have,

Thus, the value of x is 25.
(2) It is given that the measure of ∠ABC = (x+7)° and ∠CBD = (2x+14)°
Since, these two angles are supplementary angles and supplementary angles add upto 90°
Thus, we have,

Simplifying, we get,



Thus, substituting the value of x in ∠CBD = (2x+14)° to determine its value.

Thus, the measure of ∠CBD is 60°