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Graph the y = 2x ^ 2 - 12x + 15 Plot five points on the parabolathe vertextwo points to the left of the vertex, and two points to the right of the vertexThen click on the graph-a-function button

Graph the y = 2x ^ 2 - 12x + 15 Plot five points on the parabolathe vertextwo points-example-1
User Bluemagica
by
3.1k points

1 Answer

11 votes
11 votes

Explanation:

Given the function:


y=2x^2-12x+15

First, we find the vertex of the parabola.

Vertex

The equation of the axis of symmetry is calculated using the formula:


x=-(b)/(2a)

From the function: a=2, b=-12


\implies x=-(-12)/(2(2))=(12)/(4)=3

Substitute x=3 into y to find the y-coordinate at the vertex.


\begin{gathered} y=2x^2-12x+15 \\ =2(3)^2-12(3)+15 \\ =18-36+15 \\ =-3 \end{gathered}

The vertex is at (3, -3).

Two points to the left of the vertex

When x=2


\begin{gathered} y=2x^2-12x+15 \\ =2(2)^2-12(2)+15=8-24+15=-1 \\ \implies(2,-1) \end{gathered}

When x=1


\begin{gathered} y=2x^2-12x+15 \\ =2(1)^2-12(1)+15=2-12+15=5 \\ \implies(1,5) \end{gathered}

Two points to the right of the vertex

When x=4


\begin{gathered} y=2x^2-12x+15 \\ =2(4)^2-12(4)+15=32-48+15=-1 \\ \implies(4,-1) \end{gathered}

When x=5


\begin{gathered} y=2x^2-12x+15 \\ =2(5)^2-12(5)+15=50-60+15=5 \\ \implies(5,5) \end{gathered}

Answer:

Plot these points on the graph: (3, -3), (2,-1), (1,5), (4,-1), and (5,5).

Graph the y = 2x ^ 2 - 12x + 15 Plot five points on the parabolathe vertextwo points-example-1
User Vbandrade
by
2.7k points
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