The slope-intercept form of a line needs slope and a y-intercept to write.
It's a bit unclear from this problem, but I will assume that the slope is -2/3, and (-9,-5) is a point on the line.
The format of slope-intercept: y = mx + b
m = slope
b = y-intercept
So we can write y = -2/3 x + b
We have a point on the line, (-9,-5), where -9 is the x-value and -5 is the y-value of the point. We can substitute those into the equation:
-5 = -2/3 * -9 + b
which becomes
-5 = 6 + b
solve for b, and put it back here: y = -2/3 x + b
