Answer:

Step-by-step explanation:
The standard form of a quadratic equation is 
The vertex form of a quadratic equation is 
The vertex of a quadratic is (h,k) which is the maximum or minimum of a quadratic equation. To find the vertex of a quadratic, you can either graph the function and find the vertex, or you can find it algebraically.
To find the h-value of the vertex, you use the following equation:

In this case, our quadratic equation is
. Our a-value is 1, our b-value is -6, and our c-value is -16. We will only be using the a and b values. To find the h-value, we will plug in these values into the equation shown below.
⇒ 
Now, that we found our h-value, we need to find our k-value. To find the k-value, you plug in the h-value we found into the given quadratic equation which in this case is 
⇒
⇒
⇒ 
This y-value that we just found is our k-value.
Next, we are going to set up our equation in vertex form. As a reminder, vertex form is: 
a: 1
h: 3
k: -25

Hope this helps!
Answer:
-2
Step-by-step explanation:
Equation of slope intercept form
y = (slope × x) + y intercept
It would be 340%. First, you need to find out what the fraction is for 2/5. 2/5 as a decimal would be .4. Next you put that back with the three which is 3.4. After that, you need to turn that into a percentage by multiplying it by 100 which then equals 340. add the % to it and that gives you 340%.