X²+9x+a has a factor of (x+8) what is the value of 'a' equal to

Which expression is not a polynomial?

Select the correct answer from each drop-down menu. the length of a rectangle is 5 inches more than its width. the area of the rectangle is 50 square inches. the quadratic equation that represents this situation is the length of the rectangle is inches.

How do you write a paragraph proof to prove that the corresponding angles shown are congruent