This is written in the format y=mx+b, where m is the slope and b the y-intercept (the value of y when x=0).
Perpendicular lines have a slope that is the negative inverse of the slope of the reference line, in this case -(1/3). The new slope is 3. equation is:
y = 3x + b
To find b, enter the given point, (-6,-2) and solve for b: