AS we know that:

And we have the volume and we can calculate the SA,,,
So that, we can conclude:

Are you
satisfied?
I hope the choices for the numerators of the solutions are given.
I am showing the complete work to find the solutions of this equation , it will help you to find an answer of your question based on this solution.
The standard form of a quadratic equation is :
ax² + bx + c = 0
And the quadratic formula is:
x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}
So, first step is to compare the given equation with the above equation to get the value of a, b and c.
So, a = 10, b = -19 and c = 6.
Next step is to plug in these values in the above formula. Therefore,




So, 

So, 
Hope this helps you!
51 ft is the answer
Explanation
The hight of the man divided by the hight of school ( which is unknown )
Equal
The length of the shadow of the man divided by the shadow of the school
Cross multiplication and find the value of unknown x which is 51... and ya