Question

HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

Answer:  x = 9.611 ;  or ;  x = 9  11/18 .
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Explanation:
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All angles of any triangle must add up to 180 degrees.

So,  (10x - 4)  + (8x + 3) + 91 = 180 ;  Solve for "x" ; 
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    10x - 4 + 8x + 3 + 81 = 180 ;

Combine the "like terms" on the left-hand side of the equation:
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      +10x + 8x = 18x ;
        
       - 4 + 3 + 8 = 7 ;
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          18x  +  7 = 180 ;
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   Subtract  "7" from each side of the equation:
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         18x + 7 - 7 = 180 - 7 ;
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to get:  
  
         18x  = 173 ; 
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Divide EACH side of the equation by "18" ; to isolate "x" on one side of the equation;  and to solve for "x" ; 
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         18x / 18  = 173 / 18 ;
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                   x = 9.6111111111111111....
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Write as:  9.611 ;  or;   9  11/18.
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