1. y=3x^2+x-2

2. find an equation that has -5/2 and 6 as solutions

1. This is not a question.

If you are supposed to factor it, try
(3x-2)(x+1)

2. Here is one:
(x + 5/2)(x -6) = x^2 -(7/2)x -15 = 0

There are other equations that will also work.