Answer:
• Line of Symmetry: x=-0.5
,
• Vertex: (-0.5, 5.5)
,
• Maximum
,
• y-intercept: (0, 3)
Explanation:
Given the quadratic function:

Comparing with the form y=ax²+bx+c:

(a)Line of Symmetry
The equation of symmetry is determined using the formula:

(b)Next, we find the corresponding y-value.

The vertex of the parabola is (-0.5, 5.5).
(c)Since the value of a is negative, the vertex is a maximum.
(d)y-intercept
The y-intercept is the value of y when x=0.

The y-intercept is at (0, 3).