The law of cosines states that:
c^2=a^2+b^2-2abcosC
You already have all the values for the variables with the exception of x so:
x^2=25+100-100cos60
x=√(125-100cos60)
x=√75
x≈8.66 to nearest one-hundredth...
Answer: (13,-7)
Step-by-step explanation:
By using the formula 
is the coordinates of the midpoint.
For finding the midpoint X variable do:

For finding the midpoint Y variable do:
(you can either keep the parenthesis or take them out. Either way, the answer is the same.
Considering coordinate numbers follow the format: (x,y), you'll simply just substitute the numbers found above into their respective places.
x: 13
y: -7
(13,-7).
Answer: D
Example: none there is no Example
Answer is A, basically using the Pythagorean theorem but in a slightly different way, should still get you the same answer.
Answer:
use a calculator
Step-by-step explanation:
hope this helps