Answer:
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Answer:
x=amount invested at 7%
2x=amount invested at 8%
3x=amount invested at 9%
interest=principal*rate*time (time=1 year)
$150=0.07x+0.08*2x+0.09*3x
$150=0.07x+0.16x+0.27x
$150=0.50x
$1500=5x
x=$300 invested at 7%
2x=$600 invested at 8%
3x=$900 invested at 9%
Step-by-step explanation:
 
        
             
        
        
        
Answer:
The answer is X=-4 hope this helps. 
 
        
                    
             
        
        
        
that would be the letter d :) 
each value of x has a unique value of y