this is called the quadratic equation.
Either use quadratic formula to find S or The PSF
Product, sum, factor box.
Quadratic formula is : (-b±√(b²-4ac))/(2a) .
we'll use the quadratic formula because psf ain't possible.
-7± √(49-80)/2
(-7±-5.57)/2
s= 0.715 or 6.285
