Answer
Notebook each =$4
Folder each = $9
First we write out what we know
Notebook = n
Folder = f
It says a notebook is +5 than a folder so
f = n +5
It says he bought 3 notebooks and 2 folders for $30
3n + 2f = 30
Because we know from the first equation
f=n+5, we can substitute that into the second equation for f
3n + 2(n+5) = 30
3n + 2n +10 =30. Now Combine like terms
5n +10 =30. Now isolate n by subtracting 10 from both sides
5n = 20. Now isolate n by dividing both sides by 5
n = 4
Now we do the same thing to find f
We substitute the value of n (4) into the equation 3n + 2f =30
3(4) +2f =30
12 +2f =30. Now isolate f by subtracting 12 from both sides
2f = 18. Now isolate f by dividing both sides by 2
f = 9
We check our work by inserting the n and f values we found into one of the equations
n + 5 = f
4 + 5 = 9
9 = 9. It worked it equals so it’s correct
Answer:
b
Step-by-step explanation:
i dont kno lol
9514 1404 393
Answer:
- 16,965 mm/min
- 90π ≈ 282.7 radians/min
Step-by-step explanation:
The circumference of the CD is ...
C = πd
C = π(120 mm) ≈ 376.99 mm
This is the distance a point on the edge of the CD will travel when making one revolution. It will travel 45 times this far when making 45 revolutions:
(376.99 mm/rev)(45 rev/min) ≈ 16,965 mm/min
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There are 2π radians in each revolution, so the angular speed is ...
(2π rad/rev)(45 rev/min) = 90π rad/min ≈ 282.7 rad/min
Standard form: Ax + By = C
Equation: 12x + 15y = 120