Use the following general equation for a line in point-slope form:
y - yo = m(x - xo)
where m is the slope of the line and (xo,yo) any point on the line.
In this case, you have:
m = -4/3
(xo,yo) = (-6,1)
Replace the values of the previous parameters into the general equation of a
y - 1 = -4/3(x - (-6))
y - 1 = -4/3(x + 6)
The previous result is the equation in point-slope form