Went through the whole process and I got stuck at the end trying to solve the quadratic equation for the following.
8h(squared) + 9h - 4896

Question

Went through the whole process and I got stuck at the end trying to solve the quadratic equation for the following. 
8h(squared) + 9h - 4896

kropot72 · Answer

Did you use the formula for solving any quadratic?

anonymous · Answer

yes

kropot72 · Answer

What value did you get for
$$b ^{2}-4ac$$

anonymous · Answer

I dont understand the answer they gave was h = 26,24
since height cannot be negative value, -26 is not possible. the answer has to be 24. But I don't know how they came up with that answer

anonymous · Answer

Im sorry it is 12h not 9h

kropot72 · Answer

h = (-25.5, 24)
If h cannot be negative, then the positive value 24 is taken.

anonymous · Answer

how did you get that? what did you do?

kropot72 · Answer

I used the formula for solving any quadratic of the form
$$ax ^{2}+bx+c=0$$
The formula is
$$x=\frac{-b \pm \sqrt{(b ^{2}-4ac)}}{2a}$$

anonymous · Answer

thank you, I will try it a couple of times to see if I understand

kropot72 · Answer

Substituting the values in your corrected equation gives
$$h=\frac{-12\pm \sqrt{(144+156672)}}{16}$$