Answer: the speed of the current is 8 mph.
Step-by-step explanation:
Let represent the speed of the current
boat can travel 23mph in still water. This means that the total speed with which the boat travelled is (23 + x) mph.
Time = distance/speed
If it travels 248 miles with the current, it means that the time it took the boat to travel with the current is
248/(23 + x)
in the same length of time it travels 120 miles against the current. This means that the total speed with which the boat travelled is (23 - x) mph. The time it took the boat to travel against the current is
120/(23 - x)
Since the time is the same, it means that
248/(23 + x) = 120/(23 - x)
Cross multiplying, it becomes
248(23 - x) = 120(23 + x)
5704 - 248x = 2760 + 120x
120x + 248x = 5704 - 2760
368x = 2944
x = 2944/368
x = 8 mph
Answer:
D. (1, -2)
General Formulas and Concepts:
<u>Pre-Algebra</u>
- Order of Operations: BPEMDAS
- Equality Properties
<u>Algebra I</u>
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
<u>Step 1: Define systems</u>
5x - 2y = 9
3x + 4y = -5
<u>Step 2: Rewrite systems</u>
10x - 4y = 18
3x + 4y = -5
<u>Step 3: Solve for </u><em><u>x</u></em>
- Add to equations together: 13x = 13
- Divide 13 on both sides: x = 1
<u>Step 4: Solve for </u><em><u>y</u></em>
- Define: 3x + 4y = -5
- Substitute in <em>x</em>: 3(1) + 4y = -5
- Multiply: 3 + 4y = -5
- Isolate <em>y </em>term: 4y = -8
- Isolate <em>y</em>: y = -2
And we have our final answer!
Answer:
33 or 900
Step-by-step explanation:
10+18+5= 33
10x18x5=900
<h3>
Answer: Choice A</h3>
Explanation:
Notice how the input 5 leads to the output 3 when we look at the S(x) function. The inverse will undo this. So that must mean the answer is choice A where we have the input 3 lead to the output 5. In short, the inputs and outputs swap places. This means the domain and ranges swap.