Answer:
9ft
Step-by-step explanation:
Since the triangles are similar, the corresponding sides are proportional.
Let the height of the flag pole be x feet.

We multiply both sides by 6 to get:

We reduce the fraction to get:

We now simplify


-18 - 6k = 1 + 3k
-6k - 3k = 1 + 18
-9k = 19
k = -19/9 or - 2 1/9
5x -3 = 12
5x -3 + 3 = 12 + 3 [Add 3 to each side]
5x + 0 = 15 [Evaluate]
5x/5 = 15/5 [Divide each side by 5]
1x = 3 [Evaluate]
The answer I get is the number 3.
If x represents the length of the box, then 42-x will be the girth. Since the largest area for a given girth is that of a square, the side length of the square cross section is (42 -x)/4.
The volume as a function of package length is then
.. v(x) = x((42-x)/4)^2
This has a maximum at x=14. The corresponding volume is 686 in^3.
Divide -10 in 15 = -0.666666666