Hello from MrBillDoesMath!
Answer:
The first choice ( -12, 20)
Discussion:
Using matrix multiplication we find the equations:
 1x  + 1y = 8                     (A)
 2x  + 3y = 36                   (B)
Next, compute 
   2(A) - B  =>
          (2x + 2y) - (2x + 3y) = 2*8 - 36    =>
           (2x - 2x) + ( 2y-3y) = 16 - 36 =>
           -y = -20  =>
           y = 20
Substituting this y value in (A) gives
          x + 20 = 8 =>
          x = 8 - 20 =>
          x = -12
The answer is the first choice ( -12, 20)
Thank you,
MrB
 
        
             
        
        
        
Step-by-step explanation:
How are we supposed to help...?
 
        
             
        
        
        
<span>1.97 is the volume of this object
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Answer:3 & 4
Step-by-step explanation: those are the two with multiplication/division