PUMaC 2015 Algebra A Problem 2

There are real numbers a, b, c, d such that for all (x, y) satisfying 6 y^{2}=2 x^{3}+3 x^{2}+x, if x_{1}=a x+b and y_{1}=c y+d, then y_{1}^{2}=x_{1}^{3}-36 x_{1}. What is a+b+c+d ?