Answer:
π
Step-by-step explanation:
The *period* of a function is the length it takes before it repeats. Usually, the period of the sine function is 2π; it takes a full rotation around the unit circle for it to repeat. When we replace the input x with -2x, this does a few things: 
- Changes the rotation direction
- Makes the rotation go twice as fast
If we rotate around the unit circle twice as fast, it’ll take us half of 2π, or just π to complete a cycle.
 
        
             
        
        
        
Answer:
The tap drains approximately half the water from the tank in 15 minutes
The tank initially has 50 gallons of water
Step-by-step explanation:
<u>The tap drains approximately half the water from the tank in 15 minutes. </u><u>True.</u> 
This is true because see that the point (15,25) lies on the graph of the line.
Which means after 15 minutes the amount of water left in the tank is 25 gallons and 25 is half of 50.
The tap drains exactly one gallon from the tank every minute. False
This is false because the slope of the graph is 
<u>The tank initially has 30 gallons of water. </u><u>False.</u>
The y-intercept is the initial gallons of water which is 50.
<u>The tank initially has 50 gallons of water. </u><u>True.</u>
The y-intercept is the initial gallons of water which is 50.
<u>The tank takes 50 minutes to drain completely. </u><u>False</u><u>.</u>
It is false because the x-intercept tells us the tank is drained completely and it is not 50 minutes but rather 30 minutes.
 
        
             
        
        
        
Answer:
40 feet
Step-by-step explanation:
the diameter is just Rx2 (R being the radius)
 
        
             
        
        
        
We will form the equations for this problem:
(1) 1100*y + z = 113
(2) 1500*y + z = 153
z = ? Monthly administration fee is notated with z, and that is the this problem's question.
Number of kilowatt hours of electricity used are numbers 1100 and 1500 respectively.
Cost per kilowatt hour is notated with y, but its value is not asked in this math problem, but we can calculate it anyway.
The problem becomes two equations with two unknowns, it is a system, and can be solved with method of replacement:
(1) 1100*y + z = 113
(2) 1500*y + z = 153
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(1) z = 113 - 1100*y [insert value of z (right side) into (2) equation instead of z]:
(2) 1500*y + (113 - 1100*y) = 153
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(1) z = 113 - 1100*y
(2) 1500*y + 113 - 1100*y = 153 
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(1) z = 113 - 1100*y
(2) 400*y + 113 = 153 
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(1) z = 113 - 1100*y
(2) 400*y = 153 - 113
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(1) z = 113 - 1100*y
(2) 400*y = 40
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(1) z = 113 - 1100*y
(2) y = 40/400
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(1) z = 113 - 1100*y
(2) y = 1/10
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if we insert the obtained value of y into (1) equation, we get the value of z:
(1) z = 113 - 1100*(1/10)
(1) z = 113 - 110 
(1) z = 3 dollars is the monthly fee.
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
35x + 30 = 22x + 69
<u>-22x  -30    -22x  -30</u>
13x = 39
x=3