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Please help me with 6-7 / 10 points

Please help me with 6-7 / 10 points-example-1
User YAHsaves
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1 Answer

2 votes

Answer:

6) Axis of symmetry x=1. Vertex at (5,1)

7) Axis of symmetry x=1. Vertex at (1,2). y-intercept at y = -1

Explanation:

There is an equation to find the axis of symmetry of a quadratic function and is given by:

Knowing that the standard form of a quadratic equation is:


y=ax^(2)+bx+c

The axis of symmetry is:


x=(-b)/(2a) (1)

(6)

The quadratic equation of the first problem is:


y=2x^(2)-4x+7

Then, using equation (1) the axis of symmetry will be:


x=(-(-4))/(2(2))


x=(4))/(4)


x=1

We need to use this value of x to find the vertex;


y(1)=2(1)^(2)-4(1)+7


y(1)=5

The vertex is (5,1)

Therefore, we disagree with Ahmed. The axis of symmetry is x = 1 and the vertex is in the point (5,1).

(7)

We can use the same method here. The function is:


f(x)=-3x^(2)+6x-1

The axis of symmetry is:


x=(-6)/(2(-3))


x=1

The vertex is:


f(1)=-3(1)^(2)+6(1)-1


f(1)=2

So the vertex is (1,2)

We need to evaluate the function at x = 0 to get the y-intercept value.


f(0)=-3(0)^(2)+6(0)-1


f(0)=-1

Therefore, the y-intercept is at y = -1.

I hope it helps you!

User FunkSoulBrother
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