First, we are going to find the vertex of our quadratic. Remember that to find the vertex

of a quadratic equation of the form

, we use the vertex formula

, and then, we evaluate our equation at

to find

.
We now from our quadratic that

and

, so lets use our formula:




Now we can evaluate our quadratic at 8 to find

:




So the vertex of our function is (8,-72)
Next, we are going to use the vertex to rewrite our quadratic equation:



The x-coordinate of the minimum will be the x-coordinate of the vertex; in other words: 8.
We can conclude that:
The rewritten equation is

The x-coordinate of the minimum is 8
Answer:
Step-by-step explanation:
805/38= 21 7/38
So that is 21 full payments of $38.00 and one of $7.00