All you do is solve for z. So 8z-13=7. To solve for a variable you have to do the opposite to cancel out the numbers on each side. First you add 13 over to 7 to cancel out 13 on the z side. So 8z=20 is what you have left. Then you divide 8 on both sides to cancel out 8 on the z side. what you are left with is z=2.5. Lastly you plug and check. 8(2.5) - 13 = 7, 20-13=7. And thats correct so z is 2.5.
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Answer:
its12
Step-by-step explanation:
Answer:
1813.137 KJ
Step-by-step explanation:
potential energy of the body = mgH
where m is mass in Kg , g= 9.81 m/sec^2 and H= height in m
here m= 1000 kg, g= 9.81 m/s^2 and H= 607 feet = 607×0.305= 185.135 m
hence the potential energy p= 1000×9.81×185.135= 1813137.2 J
= 1813.137 KJ
hence the potential energy associated with 1 m^3 of water at 607 feet tall taking the mass as 1000 kg is = 1813.137 KJ
Change in level is given by :
C = increase in level - decrease in level.
Now,
Decrease in level in March is 2 1/4 = 9/4 inches.
Increase in level in April is 1 5/8 = 13/8 inches.
Putting value of these in above equation, we get :
C = 13/8 - 9/4
C = 13/8 - 18/8
C = -5/8 inches
Therefore, the overall level after April will decrease by 5/8 inches.
Hence, option 4. is correct.