Answer:
- first mechanic: $105/hour
- second mechanic: $55/hour
Step-by-step explanation:
Let r represent the rate charged by the first mechanic. Then 160-r is the rate charged by the second mechanic. The total of charges is ...
   20r +5(160-r) = 2375
   15r +800 = 2375 . . . . . . eliminate parentheses
   15r = 1575 . . . . . . . . . . . . subtract 800
   r = 105 . . . . . . . . . . . . . . . divide by 15. First mechanic's rate.
   160-r = 55 . . . . . Second mechanic's rate
The first mechanic charged $105 per hour; the second, $55 per hour.
 
        
                    
             
        
        
        
Answer:
x∈R
Step-by-step explanation:
 
        
             
        
        
        
the answer is circle idk if it's right but it could be I'm in high school I've been through algebra 1 now in geometry 
 
        
             
        
        
        
Answer:
(6,-4)
Step-by-step explanation:
-3x-9y = 18 (equation 1)
4x+3y = 12 (equation 2)
multiply equation 2 by 3, and add it to equation 2
-3x-9y = 18
12x+9y = 36
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X's cancel out
9x = 54
Divide both sides by 9
x = 6
Plug in 6 for x in any of the original equations
(Plugging into Equation 2) 
4(6)+3y = 12       Multiply 4(6)
24+3y = 12         Subtract 24 from both sides
3y = -12              Divide 3 on both sides
y = -4
Therefore the solution is (6,-4).