The sum of polynomials involves adding the polynomials
The other polynomial is 
The sum of the polynomials is given as:

One of the polynomials is given as:

Represent the other polynomial with Q.
So, we have:

Substitute the expressions for P and Sum

Make Q the subject

Evaluate like terms

Hence, the other polynomial is 
Read more about polynomials at:
brainly.com/question/1487158
Alternate exterior angles because the are OUTSIDE of the parallel lines
A should be the right answer. Hope this helped!
Answer:
some statements that are true are :
Step-by-step explanation:
it has only 1 line of reflectional symmetry.
a line of symmetry will connect 2 vertices.
a line of symmetry will connect a vertex and a midpoint of an opposite side.
it has 7 fold symmetry.
a line of symmetry will connect the midpoints of 2 opposite sides.