Answer:
x = 12
Step-by-step explanation:
Given a tangent and a secant from an external point to the circle, then
The square of the tangent is equal to the product of the external part and the entire secant, that is
x² = 6(6 + 18) = 6 × 24 = 144 ( take the square root of both sides )
x =
= 12
Using an exponential function, it is found that the number 131.5 represents the initial value of the plane, in thousands of dollars.
<h3>Exponential function:</h3>
A decaying exponential function is modeled by:

In which:
- A(0) is the initial value.
- r is the decay rate, as a decimal.
In this problem, the function for the value of the airplane after t years is given by:

Hence A(0) = 131.5, which means that the number 131.5 represents the initial value of the plane, in thousands of dollars.
To learn more about exponential functions, you can take a look at brainly.com/question/8935549
Answer:
? = 7.
Step-by-step explanation:
The two triangles are similar because of the AA Theorem.
The larger triangle's side that is equal to 9 + 3 corresponds to the smaller triangle's side length of 9, while the larger triangle's 21 + ? side corresponds to the smaller triangle's 21 side. Now, we can set up a proportion!




? + 21 = 7 * 4
? + 21 = 28
? = 28 - 21
? = 7
Hope this helps!