Hello, I am having trouble with this problem. I used the derivative of the equation of y=4x^3 to calculate the equation of the tangent line (also the slope), but it was marked wrong. Can you tell me what my error was and the correct answer please? Thank you.

Let { be the tangent line to the curve y = 4x at the point (1, 4). Find y. y' 12x- Find the slope m of the tangent line at the point (1, 4). 12x - 8 X Calculate o to the nearest degree. 85