m<1=123
m<1+m<2=180 (straight line)
m<1+57=180
subtract 57 from both sides
m<1=123
In this problem, it will be helpful to know the vertex form of a parabola, which is listed below:

is a constant which helps to determine whether the parabola opens up or down. If
, then the parabola opens downward and if
, the parabola opens upwards
is the vertex of the parabola
By looking at the graph, we can first see that the graph opens downwards, meaning that
. Thus, choices C and D are not valid. Now, let's use the vertex of the parabola to complete the equation.
The vertex of this parabola is (-1, 3), as shown by the graph. When we substitute this into our formula, we get:

The answer is a,
.
Your answer would be x = -15.8994.
To get this, you first add 7 to each side making the equation -4.818 = x/3.3
Then, you would need to multiply each side by 3.3 to get x by itself.
Your answer would be -15.8994.