Answer:
When x = 8, our y-value is equal to 13.
Step-by-step explanation:
We are given a graph that shows a linear relationship between our variables x and y.
In math, the slope-intercept form of an equation is written as:
[tex]\bullet \ y=mx+b, \text{where m is our slope and b is our y-intercept.}[/tex]
We also can note that there is another way to state a function: [tex]f(x)[/tex]. This replaces the y in the slope-intercept form and they can be used interchangeably.
[tex]\bullet \ f(x) = mx + b[/tex]
So, when we look at our graph, we can see that we have x-values on the bottom horizontal axis and y-values on the left vertical axis.
When we check this, we see that our x-values range from 0 to 9 and our y-values range from -2 to 14.
Therefore, we can see that since x is supposed to be equal to 8, we are going to draw a vertical line from x = 8 and see what point this intersects.
We see that the line would intersect the rightmost point and it is located between y = 12 and y = 14.
Therefore, we can just take the median of these two values and find our y value.
[tex]\displaystyle 12 + 14 = 26\\\\\frac{26}{2} = 13[/tex]
Therefore, y is equal to 13 and our answer is Choice D.
