I need help please urgent

What is f(3) for the quadratic functionf(x)=2x2 + x – 12? f -3g 3h 6i. 9

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

One month, a music site observed that 60% of the people who downloaded songs from its site downloaded q sam's latest single. the equation below represents this information, where x represents the total number of people who ddownloaded songs from the site that month: x = 0.6x + 384 how many people who downloaded songs from the site that month downloaded q sam's latest single?