When a parabola opens upward, we call the y-value of the vertex the minimum value of the function. Why do you think we call it the minimum value?
When a parabola opens downward, we call the y-value of the vertex the maximum value of the function. Why do you think we call it the maximum value?
Pick out any quadratic equation from the lessons you’ve studied so far. Type the equation in your post and tell the vertex. Does the equation have a minimum or maximum value and what is it?

im studying quadratics and radicals

Question

When a parabola opens upward, we call the y-value of the vertex the minimum value of the function.  Why do you think we call it the minimum value?
When a parabola opens downward, we call the y-value of the vertex the maximum value of the function.  Why do you think we call it the maximum value?
Pick out any quadratic equation from the lessons you’ve studied so far.  Type the equation in your post and tell the vertex.  Does the equation have a minimum or maximum value and what is it?

im studying quadratics and radicals

callisto · Answer

When it opens upwards
|dw:1332762324807:dw|
The vertex is at the lowest point of the graph so it is the min. value,
Can you work out the graph opening downwards? (just the reverse)