Question 1 of 10

Complete the square to rewrite [tex]y = x^2 - 6x + 14[/tex] in vertex form. Then state whether the vertex is a maximum or minimum and give its coordinates.

A. Maximum at [tex](-3, 5)[/tex]
B. Minimum at [tex](-3, 5)[/tex]
C. Maximum at [tex](3, 5)[/tex]
D. Minimum at [tex](3, 5)[/tex]



Answer :

To complete the square and rewrite the quadratic equation [tex]\(y = x^2 - 6x + 14\)[/tex] in vertex form, follow these steps:

### Step 1: Identify the quadratic and linear coefficients
In the equation [tex]\(y = x^2 - 6x + 14\)[/tex], the quadratic coefficient (the coefficient of [tex]\(x^2\)[/tex]) is 1, and the linear coefficient (the coefficient of [tex]\(x\)[/tex]) is -6.

### Step 2: Half the linear coefficient and square it
Take the linear coefficient, -6, divide it by 2, and then square the result:
[tex]\[ \left(\frac{-6}{2}\right)^2 = (-3)^2 = 9 \][/tex]

### Step 3: Add and subtract this square inside the equation
Add and subtract 9 within the quadratic expression:
[tex]\[ y = x^2 - 6x + 9 - 9 + 14 \][/tex]

### Step 4: Rewrite the equation as a perfect square trinomial
Now, combine the first three terms into a perfect square trinomial, and combine the constants:
[tex]\[ y = (x^2 - 6x + 9) + (14 - 9) \][/tex]
[tex]\[ y = (x - 3)^2 + 5 \][/tex]

### Step 5: Express the quadratic in vertex form
The equation is now in the vertex form:
[tex]\[ y = (x - 3)^2 + 5 \][/tex]

### Step 6: Identify the vertex
In the vertex form [tex]\(y = a(x - h)^2 + k\)[/tex], the vertex of the parabola is [tex]\((h, k)\)[/tex]. Here, [tex]\(h = 3\)[/tex] and [tex]\(k = 5\)[/tex]. Thus, the vertex is [tex]\((3, 5)\)[/tex].

### Step 7: Determine if it is a maximum or minimum point
The coefficient of the [tex]\((x - 3)^2\)[/tex] term is positive (1), indicating that the parabola opens upward. Therefore, the vertex represents a minimum point.

### Conclusion
The vertex of the quadratic equation [tex]\(y = x^2 - 6x + 14\)[/tex] is at [tex]\((3, 5)\)[/tex], and it represents a minimum point.

So, the correct answer is:
D. Minimum at [tex]\((3, 5)\)[/tex].