8• (5+x) < 56
That is the equation
        
             
        
        
        
Answer:
740
Step-by-step explanation:
The n th term of an arithmetic series is
 = a₁ + (n - 1)d
 = a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₃ = 7 and a₇ = (3 × 7) + 2 = 21 + 2 = 23 , then
a₁ + 2d = 7 → (1)
a₁ + 6d = 23 → (2)
Subtract (1) from (2) term by term
4d = 16 ( divide both sides by 4 )
d = 4
Substitute d = 4 into (1)
a₁ + 2(4) = 7
a₁ + 8 = 7 ( subtract 8 from both sides )
a₁ = - 1
The sum to n terms of an arithmetic series is
 =
 =  [ 2a₁ + (n - 1)d ] , thus
 [ 2a₁ + (n - 1)d ] , thus
 =
 =  [ (2 × - 1) + (19 × 4) ]
 [ (2 × - 1) + (19 × 4) ]
      = 10(- 2 + 76) = 10 × 74 = 740
 
        
             
        
        
        
Answer:
See Explanation
Step-by-step explanation:
<u>Define the variables</u>
Let the entry fee be c and the hourly rate be m
Let the number of hours be x and the total amount be y
<u>Work to solve</u>
For Sami's skate
 and
 and 
For Brad's skate
 and
 and 
<u>The equations</u>
The equation is derived using: 
For Sami's skate

For Brad's skate

<u>When the cost are the same</u>
To do this, we equate both expressions
i.e.




i.e. the cost are the same at the 4th hour
<u>What is the cost</u>
Substitute 4 for x in any of the equations



<em>The cost is $14.00</em>
 
        
             
        
        
        
Answer:
is that math????????????????