Ineed a little extra with number three

The answer to your question is:

Step-by-step explanation:

Data

f(x) = -2x² + 8x - 2

Process

                -2x² + 8x = y + 2

                -2(x² - 4x + 4) = y + 2 - 8

                -2(x - 2)² = y - 6

                    (x - 2)² = 1/2 (y - 6)

Vertex = (2, 6)

Axis of symmetry =   x = 2

y-intercept

                 f(0) = -2(0)² + 8(0) - 2

                 f(0) = 0 + 0 - 2

                 f(0) = -2

Domain    (-∞, ∞)

Range    (-∞, 6]

See the graph below

step-by-step explanation:

25/14 or 1.

step-by-step explanation:

the dots mean that it has infinitely more numbers behind it