Which of the following could be the equation for a parabola that opens to the left with vertex (-17,2)? a. y=3(x+17)^2+2 b. x=-3(y-2)^2-17 c. x=3(y+17)^2+2 d. y=3(x-2)^2-17

A sideways opening parabola is in the form , so we know from the process of elimination that it will either be b or c.  Next we have to realize that if the parabola opens to the left it is a negative parabola, just like if a parabola opens upside down it is a negative parabola.  So the one that has the negative out front is b. 

The correct answer is -4