Answer:
t = 14.82 and 2.72secs
Step-by-step explanation:
Given the function of the rocket height expressed as;
h(t) = -4.9t^2+ 86t + 2.1
if the rocket height is at 200m, then;
200 = -4.9t^2+ 86t + 2.1
multiplying through by 10
2000 = -49t^2 + 860t + 21
49t^2 - 860t - 21 + 2000 = 0
49t^2 - 860t + 1979 = 0
Factorize
t = 860±√(860)²-4(49)(1979)/2(49)
t = 860±√739,600-387,884/98
t = 860±√351,716/98
t = 860±593.06/98
t = 860+593.05/98 and 860-593.05/98
t = 1,453.05/98 and 266.94/98
t = 14.82 and 2.72secs
These are the times
The answer to this one is there is a 1/10 chance because there are ten balls and only one is a 0
BEDMAS
2^3 + 30 / (10 - 15 / 3)
Do everything in brackets first
First we do 15/3 which is = 5
Then 10 - 5 = 5
Now we have 2^3 + 30 / 5
Next we will do exponents so we simplify 2^3 which is the same as 2×2×2 = 8
8 + 30 / 5
Next we do division so 30/5 = 6
Finally, 8 + 6 = 14
What’s the question? I just see dots