Answer:
0.9043secs and 0.3456secs
Step-by-step explanation:
Given the height of an overhand volleyball modeled as h=-16t^2+20t+6.
If the height is 11feet, then;
11 = -16t^2+20t+6.
-16t^2+20t+6 - 11 = 0
-16t^2+20t-5 = 0
Multiply thriugh by -1
16t^2-20t+5 = 0
Factorize
t = 20±√20²-4(16)(5)/2(16)
t = 20 ±√400-320/32
t = 20 ±√80/32
t = 20 ±4√5/32
t = 20±8.94/32
t = 28.94/32 and 11.06/32
t = 0.9043 and 0.3456
Hence the required time are 0.9043secs and 0.3456secs
Answer:
c
Step-by-step explanation:
1 1/2 x1 1/2 x1 =2 and 1/4
2 and 1/4 x 8=18
The answer to the question is b
Answer:
x= 7.87298334621 x=.12701665379
Step-by-step explanation:
This is in standard form so we have to factor this into
x^2-8x + 16 + 1 = 16
(x-4)^2 = 15
(x-4) = 
x-4= ± 3.87298334621
x-4 = 3.87298334621 x-4= -3.87298334621
x= 7.87298334621 x=.12701665379
Answer:
47 ducks and 7 cows
Step-by-step explanation:
Ducks have 2 legs and cows have 4 legs.
If all the animals are ducks,
number of legs= 54(2)= 108
Difference in number of legs= 122 -108= 14
Difference in no. of legs per animal= 4 -2 = 2
Number of cows=14 ÷2 = 7
Number of ducks= 54-7= 47
Thus, he have 47 ducks and 7 cows.
Let's check:
Total number of feet= 7(4)+ 47(2) = 122 ✓
You could also first assume that all the animals are cows. The answer would be the same.