Answer: 
Step-by-step explanation:
Observe in the figure given in the exercise that four right triangles are formed.
In this case you can use the following Trigonometric Identity to solve this exercise:
From the figure you can identify that:

Then, you can substitute values:

The next step is to solve for DE in order to find its value. This is:

Finally, rounding the result to the nearest tenth, you get that this is:

Answer:
The answer to this is B.
Step-by-step explanation:
Anytime a number/variable is squared by a 0, it always equals a 1.
Hope this Helped!!!
~Shane
Subtract 4 from both sides
y−4≤−2x
Divide both sides by −2
- y-4/2 ≥ x
Switch sides
<span>x ≤ − y−4/2<span><span><span><span><span></span></span></span>
HOPE THIS HELPS!!
</span></span></span>
-17 -35
-3 -3
-2 0
-31 -87
17 57