Answer:
Step-by-step explanation:
5a - 9 + a = 9
6a - 9 = 9
6a = 9 + 9
6a = 18
a = 18/6
a = 3 <=====
The question is somewhat confusing but assuming you mean where the submarine is after moving up 7 meters then down 38 meters the submarine would now be located 56 meters below sea level

<em>If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up (+1).</em>
<em>If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down (no change).</em>
Slope -2/3
Y Intercept 2
Slope1
Y Intercept 2