Based on the given condition Diego utilized, it can be said that he used multiplication property when he multiplied both sides of the equation by 6 and then substitution property when he substituted 6 to the original equation.
(c) Multiplication property of equality and substitution property of equality
When you arrange the N points in sequence around the polygon (clockwise or counterclockwise), the area is half the magnitude of the sum of the determinants of the points taken pairwise. The N determinants will also include the one involving the last point and the first one.
For example, consider the vertices of a triangle: (1,1), (2,3), (3,-1). Its area can be computed as
(1/2)*|(1*3-1*2) +(2*-1-3*3) +(3*1-(-1)*1)|
= (1/2)*|1 -11 +4| = 3
You can solve this in two ways.
1. Graphical. Plot the graph for x between -5 and 1 (see attachement).
The vertex of the graph is the peak of the curve, which has the coordinates x=-2, y=-9.
2. Analytical. Calculate the derivative of the function f(x)

Solve the equation:

will give the solution x=-2.
Replace x=-2 in the f(x) function and you'll get the value of y:

You get the same answer: x=-2, y=-9
So the answer is
<span>B. (-2, -9)</span>
I hate study island lol and are those supposed to be powers? Like 3 to the power of 8