Answer: 40
Step-by-step explanation:
because I just had that on my math test and got it wrong
Answer:

General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra II</u>
- Distance Formula:

Step-by-step explanation:
<u>Step 1: Define</u>
Point (3, 0)
Point (3, -7)
<u>Step 2: Find distance </u><em><u>d</u></em>
- Substitute:

- Subtract:

- Exponents:

- Add:

- Evaluate:

Time =(distance)/speed
Time taken by the raft going with the current to travel x miles is:
12/x hours
Time taken by the raft going against the wind is:
7/y
Total time taken for both raft is 4 hours thus:
12/x+7/y=4
hence the answer is:
<span>D. x/12 + y/7 = 4</span>