Answer: " x = 5 " .
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Step-by-step explanation:
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(2x + 10) + (x - 4) = 21 ; Solve for x :
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2x + 10 + x - 4 = 21 ;
On the "left-hand-side" of the equation;
combine the "like terms:
+2x + x = + 3x ;
+ 10 - 4 = + 6 ;
and rewrite the equation:
3x + 6 = 21 ;
Subtract "6" from each side of the equation:
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3x + 6 - 6 = 21 - 6 ;
to get:
3x = 15 ;
Now, divide each side of the equation by "3" ;
to isolate "x" on one side of the equation;
& to solve for "x" ;
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3x / 3 = 15 / 3 ;
to get:
" x = 5 " .
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Hope this answer—and explanation—is helpful to you!
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