Respuesta :

The answer is:  " 3 m " .   The sail is:  " 3 meters tall". 
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Area of triangle, "A", equals "(1/2)" * (base) * (height) :
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  A = (1/2) * b * h ; 
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Given:  "A = 3.75 m² " ;  AND:
             "b = 2.5 m " ;  
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Solve for "h"  ;
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Given:  A =  
(1/2) * b * h ; 
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Rearrange the equation to isolate "h" on one side of the equation;
       Then, plug in the "known values" to solve for, "h" ;
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Given:  A = (1/2) * b * h ;
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Rewrite as:
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            A = (b*h) / 2 ;
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Now, multiply EACH side of the equation by "2" ; 
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                 2 *A = { (b*h) / 2 } * 2 ;
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  To get:   2A = b * h ; 
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Now, divide EACH side of the equation by "b", to isolate "h" on one side             of the equation (and ultimately, solve for "h") ;
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               2A / b = (b * h) / b ; 
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  to get:   2A / b = h ;  ↔  h = 2A / b ;
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Now, we have:   h = 2A / b ; plug in the values given for "A" and for "b" ; 
        to solve for "h" ; 
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    h = [ 2*(3.75 m²) ] / 2.5 m = 7.5 m² / 2.5 m = 3 m.
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The answer is:  3 m .   The height is:  3 m .
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