Set up a proportion.
The total side of the “top” line is 8 + 10 = 18. The total side of the “bottom” line is 45. This makes the ratio 18/45.
Now we are trying to find the “larger” bottom segment, let it be x. Because the lines are parallel, the ratio of the “larger” top and bottom segments is equal to the ratio of the whole top and bottom lines.
So 18/45 = 10/x
Reduce 2/5 = 10/x
Cross multiply 2x = 50
Solve x = 25
Answer:
and 
Step-by-step explanation:
The ratios of sine and cos are defined as follows:
, and

The hypotenuse is always the side opposite of the 90 degree angle (for the given triangle, the hypotenuse is 85)
Since we are looking at the angle A, the opposite side with respect to A would be the side length of 84. That leaves the side 13 as the adjacent side.
Thus, we can now write:


The correct answer is the first answer choice.
Make a change of coordinates:


The Jacobian for this transformation is

and has a determinant of

Note that we need to use the Jacobian in the other direction; that is, we've computed

but we need the Jacobian determinant for the reverse transformation (from

to

. To do this, notice that

we need to take the reciprocal of the Jacobian above.
The integral then changes to

Answer:
17 feet
Step-by-step explanation:
Since a square has 4 sides, you have to do 68 / 4 to find one of the sides.
68/4 = 17
And to check, if you add up all sides...
17+17+17+17 = 68
What exactly was the purpose of posting this?