It should be -3, you have to plug the points into the slope formula
The answer is letter C which is 40/41. If you draw a triangle the sides found in the cos C is BC which is equal to 40 and the CA which is equal to 41 or the 40/41. It can not be the AB since it is in the opposite side of the cos C.
6. Consecutive interior, k
7. Alternate exterior, m
8. No relationship, k
9. Corresponding, j
10. Alternate interior, l
11a 131, vertical angles
b 49, linear pair
c 131, corresponding angles
d 49, corresponding angles
e 131, vertical angles
f 49, vertical angles
g 49, vertical angles
h 92, linear pair
i 88, vertical angles
j 92, corresponding angles
k 88, corresponding angles
l 92, vertical angles
m 88, vertical angles
n 92, vertical angles
We are given expression: 
3a^3x is in front of Parenthesis.
So, we need to apply multiplication operation there.
We need to multiply like terms( numbers by number and variables by variables).
First we multiply 3 * 4, it gives 12.
Now, a^3 * a^2. In order to multiply a^3 * a^2, we need to apply product rule of exponents.
According to product rule of exponents, when bases are same, we just need to add the exponents by keeping same base.
Therefore, 
=
On the same way, we can apply apply product rule of exponents on multiplication of
x and x^3.
Therefore, final answer would be
.
I guess you multiply everything times "x", the Xs cancel out, then you will have " a + b = 1x " basically the one does not make any change, so you will end with a " a + b = x "
