This is from our problem set.

f(x)= 2(x^3)-3(x^2)-12x+20

write an equation of the line perpendicular to the graph of f at x=0

I think i'm supposed to take the derivate of f and then find the slope of the tangent line at x=0. Then take the opposite reciporcal of that and put this slope and the point (0,20) into point-slope from to get the equation but i'm not exactly sure if this is write. So, can someone help me.

Thank YOu