He made a mistake in step #2. It seemed to be a trivial mistake because it involved signs, but it still had a great impact. Since step#2, his solution was already wrong.
Instead of
(-1)²-4(2)(-6) = 1 + 48 = 49
What he did is
(-1)²-4(2)(-6) = -1 + 48 = 47
Answer: a) 
Step-by-step explanation:
We know that the volume of an oblique pyramid is given by :-

If the volume of an oblique pyramid with a square base is V units³ and the height is h units.
Then, we have

Multiply 3 on both sides , we get

Divide both sides by h , we get

i.e. 
Hence, the expression represents the area of the base of the pyramid = 
Hence, the correct answer is a) 3 v/h units^2
Answer:
(Add one then subtract one)
Step-by-step explanation:
O2, or Oxygen, and C6H12O6, or glucose.