Answer:
Rita had r apps as the start of the day
After she deleted 5 apps, 
equation for apps of cora = (r-5)
Equation for apps of Rita = 2 (r-5)
Step-by-step explanation:
 
        
                    
             
        
        
        
Answers: 
x = 4
EF = 14
CF = 7
EC = 7
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Work Shown:
C is the midpoint of segment EF. This means that EC = CF. In other words, the two pieces are congruent. 
Use substitution and solve for x
EC = CF
5x-13 = 3x-5
5x-13+13 = 3x-5+13
5x = 3x+8
5x-3x = 3x+8-3x
2x = 8
2x/2 = 8/2
x = 4
Now that we know that x = 4, we can use this to find EC and CF
Let's compute EC
EC = 5x - 13
EC = 5*x - 13
EC = 5*4 - 13 ... replace x with 4
EC = 20 - 13
EC = 7
Let's compute CF
CF = 3x - 5
CF = 3*x - 5
CF = 3*4 - 5 ... replace x with 4
CF = 12 - 5
CF = 7
As expected, EC = CF (both are 7 units long).
By the segment addition postulate, we can say EC+CF = EF
EC+CF = EF
EF = EC+CF
EF = 7+7
EF = 14
        
             
        
        
        
Answer:
(-10,-4)
Step-by-step explanation:
The point is moved to the other side of the y axis.
The y coordinate would stay the same and the x coordinate would move the same number of units but on the opposite side (that's why its -10).
 
        
             
        
        
        
Answer:
f(3)= 33
Step-by-step explanation:
hello : 
f(x) =8x+9
put x = 3    you have : f(3) =8(3)+9 = 24 + 9 =33
 
        
             
        
        
        
 220. Think of it this way: 5 and above, give it a shove, 4 and below, keep it down low. That means that if the last number is five or above, push it up to the nearest 10, and if the last number is four or below, round to the lowest 10.