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

The answer is 9.7 cm