I can do the solution, I do not understand the theory! Here it is: Using a pendulum to determine g using T = 2π√(l/g) (that little n looking thing is pi) (given l and T) So, then we get T^2 = (4π^2/g) x l This is where I get lost. Supposedly, I am to make the equation T^2 = kl (where k is the group of constants) Then, I am to compare this formula with the general equation for a straight line y=kx. Thus, k = m (of a graph, where vertical T^2 and horizontal l is the axis) Why/how does k = m ? k being (4π^2/g) and m being the gradient of my graph? ______________ Thank you!