Answer:
it's 7.5
Step-by-step explanation:
1/2 as a decimal is 0.5
i need a photo like stooooopidd
Answer:
t≈8.0927
Step-by-step explanation:
h(t) = -16t^2 + 128t +12
We want to find when h(t) is zero ( or when it hits the ground)
0 = -16t^2 + 128t +12
Completing the square
Subtract 12 from each side
-12 = -16t^2 + 128t
Divide each side by -16
-12/-16 = -16/-16t^2 + 128/-16t
3/4 = t^2 -8t
Take the coefficient of t and divide it by 8
-8/2 = -4
Then square it
(-4) ^2 = 16
Add 16 to each side
16+3/4 = t^2 -8t+16
64/4 + 3/4= (t-4)^2
67/4 = (t-4)^2
Take the square root of each side
±sqrt(67/4) =sqrt( (t-4)^2)
±1/2sqrt(67) = (t-4)
Add 4 to each side
4 ±1/2sqrt(67) = t
The approximate values for t are
t≈-0.092676
t≈8.0927
The first is before the rocket is launched so the only valid answer is the second one
Answer:
Step-by-step explanation:
This is simply a units conversion problem. It gives us for the number of passengers, the number of seats per carriage and the number of carriages per train. To change the units from passengers to trains without changing the value, we use the multiplicative identity (that is, 1).
350000 passengers
(350000 passengers) * 1
(350000 passengers) * ((1 carriage)/(32 passengers)) * ((1 train)/(15 carriages)
[note: passengers and carriages cancel. Leaving only trains]
(350000)*(1/32)*(1/15) trains [note: I write this way to paste into MS Excel]
729.1667 trains [oh, but don’t just round this number either up or down]
729 full trains can carry 729*32*15 = 349920 passengers
730 full trains can carry 730*32*15 = 350400 passengers
Now, we can say that 730 trains are adequate to carry 350000 passengers.
2x-y =3
multiply by 4
8x - 4y = 12
3x +4y = 10 (unchanged equation)
------------------add
11x = 22
answer is A. the first.
first equation multiplied by 4 then sum to get 11x = 22
