explain the math I would use to arrive at that answer?

2x^2 − 4x = t

In the equation above, t is a constant. If the equation has no real solutions, which of the following could be the value of t ?

a) -3

b) -1

c) 1

d) 3

I already know the correct answer to the question is A, but I don’t have any idea how to find that answer. Can you explain the math I would use to arrive at that answer? This question is from SAT 6 from the College Board, section 3 question 13.