The vertex of this parabola is at (-3,-1). when the y value is 0, the x value is 4. what is the coefficient of the squatted term

I'm assuming by the way those points lie in the coordinate plane that this is a parabola that opens to the right, a y^2 parabola.  Our x and y coordinates are (4,0), and the h and k of the vertex are (-3, -1).  The standard form for this parabola is .  We need to find a.  Filling in accordingly, .  Simplifying a bit we get 4 = a - 3.  a = 7.  The parabola, then, has the equation

A’b’c’ are the coordinates to the new location of the transformed triangle abc. find the distance between the coordinates points to use for your calculations.