- 52 x 1/5 + 4 = - 6.4
-12 x 1/5 - 4 = -6.4
The answer is 1/5
What we know:
(Also, 
)
What we need to solve:
(This is equal to 
)
How you have to subtract 
with 
to get:
Thus, the answer would be:
Answer:
- KEi = 2.256×10^5 J
- KEf = 9.023×10^5 J
- 4 times as much work
Step-by-step explanation:
The kinetic energy for a given mass and velocity is ...
KE = (1/2)mv^2 . . . . . m is mass
At its initial speed, the kinetic energy of the car is ...
KEi = (1/2)(810 kg)(23.6 m/s)^2 ≈ 2.256×10^5 J . . . . . m is meters
At its final speed, the kinetic energy of the car is ...
KEf = (1/2)(810 kg)(47.2 m/s)^2 ≈ 9.023×10^5 J
The ratio of final to initial kinetic energy is ...
(9.023×10^5)/(2.256×10^5) = 4
4 times as much work must be done to stop the car.
_____
You know this without computing the kinetic energy. KE is proportional to the square of speed, so when the speed doubles, the KE is multiplied by 2^2 = 4.
Answer:
Bidmas(brakets-indices-division-multiplication-addtion-subtraction) therfore
4*3-6+5=12-6+5=12-1=11
