Answer:
D. Up
Step-by-step explanation:
When a parabola has the form
, It is vertical (opens up or down).
Because the variable "x" is squared.
If "a" is positive, then the parabola opens up, but if it is negative, then the parabola opens down.
In this case you have the quadratic function:

Which can be rewritten as:
Therefore, it is vertical, because it has the form: 
You can observe that the value of "a" is:

Then, since "a" is positive, the parabola opens up.
Add numbers with the same amount of variables
-x^2 + (-7x^2) = -8x^2
– 28x (+ 14x )= -14x
7 (+ 8) = 15
-18x² - 14x + 15 is your answer
hope this helps
Option A:

Solution:
Given data:
Center of the circle is (5, 3).
Radius of the circle = 4
To find the equation of the circle:
The general form of the equation of a circle in centre-radius format is

where (h, k) is the centre of the circle and r is the radius of the circle.
Substitute the given values in the equation of a circle formula:


The equation of the given circle is
.
Hence Option A is the correct answer.
The second option is the right one
Answer:
Step-by-step explanation:
17.3664