A. is true because 2+2 does = 4 and 1 +1 =2
B is false because 2 +3=5
yes, it is since none of the x's are repeated as with the y's
Answer:

Step-by-step explanation:
The Law of Cosines works for any triangle and is given by:
, where
,
, and
are the sides of the triangle and
is the angle opposite to
.
In the given triangle, assign the variables:
Substituting these variables, we have:

The answer is 7850 centimeters since 1m=100 cm. 78.5*100=7850