(-5,2) concave up
Hope this helps :)
There are several approaches.
(5/3)x^2 - 5 = 0 has the coefficients a=5/3, b=0 and c = -5.
Thus, the quadratic formula would be appropriate here:
-0 plus or minus sqrt(0^2 - 4(5/3)(-5) )
x = -------------------------------------------------------
2(5/3)
plus or minus sqrt(100/3)
= ------------------------------------
10/3
3 10
= ------* ----------- = sqrt(3) (answer)
10 sqrt(3)
2.5 miles per hour
Because 3/4 divided by 3/10 is equal to 2.5
