Since y is equal to two different expressions, we can equate the expressions: -x^2-2x-2=x-4. This can be rewritten by combining like terms: x^2+3x-2=0. This can be solved using the quadratic formula, so x=(-3+sqrt(9+8))/2=(-3+sqrt(17))/2=0.56155 or -3.56155. From this we get two values of y: -3.4384 or -7.56155.