hello i need help with this problem ..

given f(x)=x^2-2x

a) find f'(x)..

• the answer is f'(x) = 2x-2

B) find the slope of the lines tangent to the graph of f at x=-3, 0 and 2

• when x= -3 it is -8
• when x= 0 it is -2
• when x= 2 it is 2

C) graph f, and sketch in the tangent lines at x= -3, 0 and 2

can you please help me with c?