Equation of line is given as y=mx+c, where m is gradient and c is the y-intercept.
Parallel lines have the same gradient so gradient = -4
Eqn: y = - 4x + c
Since the line passes through C(1,6), subt the coordinates into the equation to find y-intercept.
6 = -4(1) + c
c = 6+4 = 10
Hence, the equation of the line is y = - 4x + 10