Equation (1)
Equation (2)
Get y alone in equation (1)
Insert y in equation (2)
Is odd between 5 and 40 is a square number and the digits add to 7.
all the square numbers between there are 9,16, 25, 36
It's not 9, 16 or 36 so it has to be 25
Hope this helps :)
Are you solving for x or what
Answer:
Speed of plane in still air: 490 mile/hour
speed of wind: 70 mile/hour
Step-by-step explanation:
still speed = x wind speed = w
with wind: speed = still + wind
(x+w) * 3 = 1680 ...a
against wind: speed = still - wind
(x-w) * 4 = 1680 ...b
b-a ... 4x-4w-3x-3w = 0
x-7w = 0
x = 7w
substitution: (7w+w)*3 = 1680 8w = 560 wind speed (w) = 70
still speed (x) = 7w = 490 mile/hour
Answer:
By using the energy conservation law, the input energy must be equivalent to the output energy. If you measured output energy is lower than your input energy, you have lost that difference of energy either in mechanical inefficiency (friction, heat, etc.) or an energy sink.
Thus, the energy not output by the machine is lost in the process within the machine.
Cheers.
