Answer and explanation:
To find : Calculate to the nearest 1/10th meter the length of the side of a 7th, 12th, and 30th hectare square plot.
Solution :
The area of the square is given by,
where s is the side length.
We know, 
1) The area of square plot is 7 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 264.8 meter.
2) The area of square plot is 12 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 346.4 meter.
3) The area of square plot is 30 hectare.
Area in meter square is 
Substitute the value in the formula,
Side nearest to 1/10th meter is 547.7 meter.
Answer: x = 4 and y = -3
Step-by-step explanation:
2x + 4y = -4
2x = -4 - 4y
x = -2 - 2y
Now that we have solved the first equation for x, we plug (-2 - 2y) into the other equation in place of x and then solve for y.
3(-2 -2y) + 5y = -3
-6 - 6y + 5y = -3
-y = 3
y = -3
Now that we know y, we plug it into the original equation and solve for x.
2x + 4(-3) = -4
2x + -12 = -4
2x = 8
x = 4
You can check the answer by plugging both x and y into either of the original equations.
In a mechanical system, it is a law that energy should be conserved. In this case, what is the initial energy should be equal to the total energy after the motion happened. We do as follows:
PE(at rest) = KE(during motion) + PE(after motion)
51450 J = KE(during motion) + 32781 J
KE(during motion) = 18669 J
0789 is the smallest
9870 is the largest