Question

PLEASE HELP! I will give brainliest

Answer 1

3 Answers:

A) y intercept is (0,3)

C) Axis of symmetry is x = -1

D) Vertex is (-1, 4)

So basically everything but choice B is true.

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Explanation:

Choice A is true because plugging in x = 0 leads to y = 3. Effectively, anything with an x goes away when x = 0 leaving that 3 behind. So finding the y intercept in this form is fairly fast.

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To check choices B through D, let's convert the equation into vertex form.

y = -1x^2 - 2x + 3 is in the form y = ax^2 + bx + c where

a = -1

b = -2

c = 3

The vertex is located at (h,k) such that h = -b/(2a)

Plug the values of 'a' and 'b' into the equation below

h = -b/(2a)

h = -(-2)/(2*(-1))

h = 2/(-2)

h = -1

The x coordinate of the vertex is x = -1

Then use this to find the y coordinate of the vertex

y = -1x^2 - 2x + 3

y = -1(-1)^2 - 2(-1) + 3

y = 4

The y coordinate of the vertex is 4, meaning k = 4

The vertex overall is (h,k) = (-1, 4)

This shows choice D is true, meaning choice B has to be false.

Choice C is true because the axis of symmetry is the x coordinate of the vertex. This is the vertical line that cuts the parabola into two mirrored halves. This vertical line always goes through the vertex.