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PLEASE HELPPP!!!!

1. ) The points (-2, 6), (-1, 3), (0, 2), and (1, 3) are on the graph of my function. What is the equation?

2. ) My parabola intersects the x-axis at points (-2, 0) and (2, 0) and the y-axis at point (0, -4). What is the equation?

3.) The table of values below describe the relationship for my function.

x values: -2, -1, 0 , 1
y values: 4, 1, 0, 1

What is the equation?

4.) To find my equation, shift f(x) = x2 + 5 left 3.

What is the equation?

User Davs
by
3.2k points

1 Answer

5 votes

Answer:

1)
y=x^2+2

2)
y=x^2-4

3)
y=x^2

4)
y=x^2+6x+14

Explanation:

Question 1

Given points: (-2, 6) (-1, 3) (0, 2) (1, 3)

This is likely to be a quadratic equation with a vertex of (0, 2) since the points (-1, 3) and (1, 3) are symmetrical about x = 0

Vertex form of quadratic equation:
y=a(x-h)^2+k

(where (h, k) is the vertex)


\implies y=a(x-0)^2+2


\implies y=ax^2+2

To find a, input one of the points into the equation:


(1, 3)\implies a(1)^2+2=3\implies a=1

Therefore, the equation of the graph is
y=x^2+2

Question 2

If the parabola intersects the x-axis at (-2, 0) and (2, 0) then


y=a(x+2)(x-2)

We are told that the y-intercepts if (0, -4). Input this into the equation to find a:


\implies a(0+2)(0-2)=-4


\implies -4a=-4


\implies a=1

Therefore,


\implies y=(x+2)(x-2)


\implies y=x^2-4

Question 3

Given points: (-2, 4) (-1, 1) (0, 0) (1, 1)

This is likely to be a quadratic equation with a vertex of (0, 0) since the points (-1, 1) and (1, 1) are symmetrical about x = 0

Vertex form of quadratic equation:
y=a(x-h)^2+k

(where (h, k) is the vertex)


\implies y=a(x-0)^2+0


\implies y=ax^2

To find a, input one of the points into the equation:


(-2,4)\implies a(-2)^2=4\implies a=1

Therefore, the equation of the graph is
y=x^2

Question 4


f(x) = x^2 + 5

If we wish to move the function to the left by 3 units, we substitute x for
x+3:


\begin{aligned}\implies f(x+3) & =(x+3)^2+5\\ & = x^2+6x+9+5\\ & = x^2+6x+14\end{aligned}


\implies y=(x+3)^2+5

User Hafeez Hamza
by
3.5k points