In order to determine the equation of the given line, take into that the general form of the equation of a line is:
y = mx + b
where m is the slope of the line and b the y-intercept.
To find m use the following formula:
m = (y2 - y1)/(x2 - x1)
where (x1,y1) and (x2,y2) are two points on the line.
Use (x1,y1) = (-4,-3), (x2,y2) = (4,3):
m = (3 - (-3))/(4 - (-4)) = 6/8 = 3/4
The y-intercept is the value of y when x=0.
You can notice that such value is b=0.
Hence, the equation of the given line is:
y = 3/4x