Pemdas, so exponent before multiply
so do a^-1/2 then multiply it by 2
remember that
![x^ \frac{m}{n}= \sqrt[n]{x^m}](https://tex.z-dn.net/?f=x%5E%20%5Cfrac%7Bm%7D%7Bn%7D%3D%20%5Csqrt%5Bn%5D%7Bx%5Em%7D%20%20)
and

therefor,

the we multiply by 2
it is correct
Step-by-step explanation:
Using the given values from the problem and the illustration, three points are known which are (0,0), (6.5,-31), (-6.5,-31). The first step in solving this problem is to determine the equation of the parabola.
y = ax²
-31 = a(6.5)²
-31 = 42.25a
a = -31/42.25
a = -124/169
Therefore, the equation of the parabola is y = (-124/169)x². The value 4.5 is then substituted in the equation as x to get the answer which is 16.14 meters.
Answer:
3hours and 15 mins
Step-by-step explanation:
210 divied by 3=70
70=per hour
4 hours=280
70 divied by 2= 35
.5=35
280+35=315
315 miles in 4.5 hours