Firstly, we need to differentiate the equation to find an equation for the gradient of the line.dy/dx = 6x-12We know the original graph was quadratic, and therefore only has one stationary point. This is when the gradient is equal to 0, and so we can set dy/dx to 0 to find this coordinate.6x-12=0 6x=12x=2We can then find the y coordinate by substituting into the original equation:3*(2)2 -12*2=12-24=-12So the stationary point is at (2, -12)