PLZ HELP DUE SOON also answer my other questions

For what value of a will this equation has only one real root:
(2a-5)x²-2(a-1)x+3=0

Solve by any method (graphing, substitution or linear combination)y = x - 82x + 3y = 1a) (2, -6)b) (5, -3)c) (4, -4)d) (0, -8)i figured it out. the answer is (5, -3)

Which of the following best describes the delian problem?

What is the value of the product (3-2i)(3+2i)?