In a parallelogram, opposite angles are congruent.
This means that the four angles of the parallelogram are:

Moreover, the sum of the interior angles of a polygon with n sides is 180(n-2). So, the sum of the interior angles of a parallelogram is 360.
This means

And since
, we have 
Answer:
6x(x+2)
Step-by-step explanation:
Factor 6x out of 6x^2+12x
6x(x+2)
20 and that should be correct, if you need an explanation just ask
You multiply .15 times 60 and you get 9 i believe
The graph is shown in the attached image.