Inactive Tutor answered 05/01/20
This question is asking you to find the vertex of the parabola since it will be the highest or lowest point of the quadratic equation. First, we will calculate the x-value at the vertex using a formula, then we will plug the x-value into the quadratic equation to find the y-value of the vertex.
To find the x-value of the vertex of a quadratic function, use the formula:
-b / 2a
where b is the constant by x, and a is the constant by x2 . This is a standard formula. In this case:
a = 3
b = -30 (don't forget the negative sign!)
Now we can plug these into the formula to find the x-value of the vertex:
x-value = -b / 2a
x-value = -(-30) / (2 x 3)
x-value = 30 / 6 = 5
The x-value at the vertex is 5. To find the y-value at the vertex, plug the x-value we just found into the quadratic function:
f(x) = 3x2 - 30x + 73
f(5) = 3(5)2 - 30(5) + 73 = -2
The y-value at the vertex is -2, so our vertex is at (5,-2). Since the y-value at the vertex will always be the minimum or maximum value of a quadratic equation, -2 is the minimum or maximum value.
Please message me if you would like more explanation or have another question.
Lilly R.
Thank you05/01/20