Which binomial must be added to (2r+12) so that the sum of two polynomials is (6r-7)?

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

Which expression demonstrates the use of the commutative property of addition in the first step of simplifying the expression (-1+i)+(21+5i)+0

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?