Question

Determine the maximum or minimum value of the quadratic function from its equation.

Answer 1

Below in bold.

Explanation:

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

As the coefficient of x^2 is positive it will have a minimum value.

The minimum value is the last term = 4.

Answer 2

You'll need to multiply the function out to get it in the form y = ax^2 + bx + c, in this case it would be y = 4x^2 + 16x + 20.

We can immediately see that y = 20 would be the y value for the pivot point for the equation, and since the equation is positive it woukd have a concave shape. Thus it woulc be a minimum of 20, since there are no points lower than that on the y-axis.

Plotting functions like this on desmos helps you get a better understanding of how they work. I recommend you try! ;)