The answer is -76.1 meters.
The submarine elevation before rising is -203 meters (it is negative because it is under the sea level which has 0 elevation): d₁ = -203 m
After the first rising, it moved 64.5 m: l₁ = 4.3 · 15 = 64.5 m
After the second rising, it moved 62.4 m: l₂ = 5.2 · 12 = 62.4 m
So, to calculate the elevation of the submarine after rising (d₂), we will add (because it is not going deeper, it rises toward the elevation of 0) two movements to the elevation before rising:
d₂ = d₁ - (l₁ + l₂) = -203 + (64.5 + 62.4) = -203 + 126.9 = -203 + 126.9 = -76.1.
Your two equations for this question would be:
n + d = 234
5n +10d = 16.10
So with that you must take your two equations and make them equal to eachother.
Hope this helped :)
This answer would be (-14).
80/2= 20 then take away the extra 20 from the math for dance and you have the answer... 20 get it?
34 / .40 = 85
I hope this helps :)