Which of the following is not a function? Question 2 options:

{(1,2)(0,9)(3,4)(5,6)}

{(1,2)(3,4)(5,6)(7,8)}

{(1,5)(2,5)(3,5)(4,5)}

{(7,1)(2,4)(7,5)(8,3)}

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

Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?

Ab and bc are tangent to circle d. find x is ab = 3x + 8 and bc = 26. find x