A: To find the rate in feet per minute, we can use the information given.
Every two minutes, the submarine dives 300 feet. So

.
In order to confirm that our rate is correct, we can use the second set of information given.

=

.
Since we know that the rate is 150 feet per minute, we can multiply it by any number of minutes and get the answer of how deep the submarine is. We can use a variable x to represent the number of minutes and y to represent the depth in feet.

There's our equation.
B: It would be more reasonable to use an equation with the rate feet per minute because it is more accurate since the time interval isn't too big.
Mult. the 2nd eqn by 6 and then add this "new" equation to the 1st given eqn:
-6x + y = -2
6x -18y = 54
--------------------
-17y = 52, or y = -52/17. Subst. this value of y into either equation to find the value of x.
Answer: x = 0
y = 2
z = -1
Step-by-step explanation:
The system of equations are
x+y+z=1 - - - - - - - - - - 1
-2x+4y+6z=2 - - - - - - - - - 2
-x+3y-5z=11 - - - - - - - - - 3
Step 1
We would eliminate x by adding equation 1 to equation 3. It becomes
4y -4z = 12 - - - - - - - - - 4
Step 2
We would multiply equation 1 by 2. It becomes
2x + 2y + 2z = 2 - - - - - - - - - 5
We would add equation 2 and equation 5. It becomes
6y + 8z = 4 - - - - - - - - - 6
Step 3
We would multiply equation 4 by 6 and equation 6 by 4. It becomes
24y - 24z = 72 - - - - - - - - 7
24y + 32z = 16 - - - - - - - - 8
We would subtract equation 8 from equation 7. It becomes
-56z = 56
z = -56/56 = -1
Substituting z = -1 into 7, it becomes
24y - 24×-1 = 72
24y + 24 = 72
24y = 72 - 24 = 48
y = 48/24 = 2
Substituting y = 2 and z = -1 into equation 1, it becomes
x + 2 - 1 = 1
x = 1 - 1 = 0
Answer: 12.32 for 5 day week or 8.8 for a seven day week
Step-by-step explanation:
2.2 x 28 = 61.6
61.6 divided by 5 is 12.32
divide by seven if its a full week and the answer is 8.8
Per 1,000 units the last one