KE = 0 (because velocity is 0)
PE = mgh = 2kg*9.8m/s^2*40m= 784 joule
<u>Explanation:</u>
KE stands for kinetic energy. In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity.
Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. Since in this case, the building is still and therefore it does not have any kind of kinetic energy because there is not acceleration.
For this case you must simplify the expression respecting the rules of multiplication of mathematics.
The steps to simplify the expression are the following:
First multiply what is in the parentheses
-2x ^ 2 (x - 5) + x (2x ^ 2 - 10x) + x
-2x ^ 3 + 10x ^ 2 + 2x ^ 3 - 10x ^ 2 + x
Then add the terms that have the same exponent
(-2x ^ 3 + 2x ^ 3) + (10x ^ 2 - 10x ^ 2) + x
x
The final simplification is
x
answer
x
Ok the answer to your question is -25