The answer is: [C]: "7 m" .
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Using the formula for the perimeter of kite:
Perimeter:
P = 2(a+b) ; a = length of side "a" ; b = length of side "b";
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Given: The Perimeter, "P: = 52 m ; b = 19 m;
52 = 2(a+19) ; solve for "a" :
52 = 2a + 38 ; Subtract "38" from each side of the equation;
52 - 38 = 2a + 38 - 38 ;
to get : 14 = 2a ; ↔ 2a = 14 ;
Now, divide EACH SIDE of the equation by "2";
to isolate "a" on one side of the equation ; and
to solve for "a" ;
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2a = 14 ;
2a/2 = 14/2 ;
a = 7 m
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The answer is: " 7 m " .
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