Answer: 
Step-by-step explanation:
We need to apply the following identity:

Then, applying this, you know that for
:

We need to remember that:
and 
Therefore, we need to substitute these values into
.
Then, you get:



Answer:
Choices C and D
Step-by-step explanation:
The most simplest way is just to solve each one and see which two have the same answer as the first expression.
But you could also see that both of the
are going to cancel each other out so you are left with
which is also choice C.
For choice D I distributed the negative one to the insides of the parenthesis that left me with
which is the same expression as the first one.
Use the formula y2-y1/x2-x1.
3-3/-4-8
0/-12
The slope is 0, so the line is horizontal.
Answer:
statement: 2. both pairs of parallel lines are congruent
reason: 2. def. of a parallelogram
and that should be all you need
70º
It's a supplementary angle so 180º - 110º