y = 3x (point slope equation)
See explanation below
Step-by-step explanation:
The point slope formula:

we need to find m = slope

To get two points for calculatiing the slope, we will use the straight line graph attached to the question
From the graph, we have:
(x, y) = (0, 0), (1, 2), (-1, -2)
using points (0, 0) and (1, 2):
m = (2-0)/(1-0) = 2/1
m = 2
we insert into the point slope formula, using point (0,0)
y - 0 = 2(x-0)
y = 2x (point slope equation for the line)
If slope = m = 3
y = 3x (point slope equation)
To get the values of y given x, we insert the values of x in the point slope equation we derived.
We have values of x on the graph = -4, -2, 0, 2
when x = -4
y = 3(-4) = -12
when x = -2
y = 3(-2) = -6
when x = 0
y = 3(0) = 0
when x = 2
y = 3(2) = 6