It's none of those, but the last is quite close to the exact value. You can find approximate square roots by trial and error: for sqrt(8), 2 is too small and 3 is too big, so try 2.5, 2.6, 2.7, 2.8, and 2.9. You'll find the answer is between 2.8 and 2.9.
Answer:
The area of half of the garden in square meters.
Solve (x) F(x)=x^2+3x-2 is x-2