Select all of the following that are quadratic functions. x = 3y2 – 6y + 5

y + 3 = –2 x 2+ 5

y = 2 x 2 – 8 x + 6

y= –7 x – 4

y – 3 x = 4 x 3 – x2 + 9

y = 5 x(x + 9) – 8

y – 2 x 2 = 3 x – 2 x 2 + 4

Which of the following expressions is equal to 2x^2+8

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

What is the solution to the system of equation graphed belowa.(0,-4)b.(2,5),1),-3)