(5 + x) + 0 = 5 + x
What property is this

Me solve this problem, and someone clearly explain to me how to solve it.1.) use the value of the discriminant to determine if the given trinomials has 2 real solutions, 1 real solution, or no real solutions.a.  x2  − 4x  − 7 = 0b. 4r2  + 11r  − 3 = 0c. 3m2  + 7 = 0d.  t2  + 2t  + 1 = 0

What numbers are included in the set of integers? what numbers are not included?

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?