Which of the following shows that polynomials are closed under addition when two polynomials 4x^-8x-7 and -5x+16 are added?

•4x^-13x+9; may or may not be polynomial
•4x^+13x-23; may or may not be polynomial
•4x^-13x+9; will be a polynomial
•4x^+13x-23; will be polynomial
I need an answer quick, thank you!!

What is the slope of a line that is perpendicular to y = 3x + 1

6x - 8 = 16 solve the following equation. then place the correct number in the box provided.

The equation of a circle is (x - 3)2 + (y - 7)2 = 25. determine the length of the radius. 4 25 12.5 5 write the standard equation of the circle with center (2, 3) and a diameter of 12. (x - 2)2 + (y - 3)2 = 36 (x + 2)2 + (y + 3)2 = 12 (x - 2)2 + (y - 3)2 = 6 (x - 3)2 + (y - 2)2 = 36 the equation of a circle is (x + 3)2 + (y + 7)2 = 25. where is (3, 4) located in relation to the circle? on the circle in the interior of the circle in the exterior of the circle at the center of the circle