Answer:
=−8x2+35x
Step-by-step explanation:
multiply first
 
        
             
        
        
        
Answer:
11 hours
Step-by-step explanation:
Let's say Karen makes x hours babysitting and y hours giving music lessons.
Because she worked a total of 18 hours, we know that x + y = 18.
5 * x is how much money she earns babysitting for x hours, while 12 * y is how much money she earns giving music lessons for y hours. Adding them up gives her total revenue:
5x + 12y = 139
We now have a system of equations. Let's multiply both sides of x + y = 18 by 12:
12 * (x + y) = 18 * 12
12x + 12y = 216
Now, subtract 5x + 12y = 139 from 12x + 12y = 216:
      12x + 12y = 216
-     5x + 12y = 139
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        7x + 0y = 77
Divide both sides by 7:
x = 11
Thus, Karen spent 11 hours babysitting.
 
        
             
        
        
        
First you must make sure all measurements are in the same value: You can choose either cm or km
Distance = 1,000,000 cm or 10 km
Radius = 50 cm or 0.0005 km
Distance/(2πR)
1,000,000/(2π*50)
1,000,000/314.059…….
Approx = 3183.1 Rotations
        
             
        
        
        
This is 1/2)2=1/4 hope this helps