Step-by-step explanation:
We want to find two things-- the speed of the boat in still water and the speed of the current. Each of these things will be represented by a different variable:
B = speed of the boat in still water
C = speed of the current
Since we have two variables, we will need to find a system of two equations to solve.
How do we find the two equations we need?
Rate problems are based on the relationship Distance = (Rate)(Time).
Fill in the chart with your data (chart attached)
The resulting speed of the boat (traveling upstream) is B-C miles per hour. On the other hand, if the boat is traveling downstream, the current will be pushing the boat faster, and the boat's speed will increase by C miles per hour. The resulting speed of the boat (traveling downstream) is B+C miles per hour. Put this info in the second column in the chart. Now plug it into a formula! <u>Distance=(Rate)(Time) </u>Now solve using the systems of equations!
Answer:
100300
Step-by-step explanation:
Answer:




Step-by-step explanation:
Given:


---
1st problem:


Distribute:

Combine like terms:

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2nd problem:



Distribute -3 to first factor:
Use foil to simplify:

Replace
with -1:

Combine like terms:

---
3rd problem:


Distribute 2 to the second factor:


Use foil to simplify:

Replace
with -1:

Combine like terms:

----
4th problem:

Distribute:

Combine like terms:

Simplify:

Based on the emperical rule
the distribution will be as follows
btwn 80 n 85 on the test - 34%
btwn 80 n 95 on the test - 82%
below 85 on the test - 50%
<span>above an 80 on the test - 84%</span>