we know that
The measurement of <u>the external angle</u> is the semi-difference of the arcs which includes
so
m∠LMN=
therefore
the answer is 
You can't change more than 100 percent
First, you factor and simplify (respectively) the numerator and denominator. Your equation becomes:

Notice, there is a (x + 7) on both the top and the bottom. Because of this, they cancel each other out. What is left is your answer:
Answer:
The answer is b I'm not to sure but I think its b