Question

What values of x make the equation x2 + 9x – 22 = 0 true? Check all that apply. –11 –2 0 2 11

Answer 1

Answer: x = 2 ; -11 .
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Step-by-step explanation:
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Given the equation:
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x² + 9x − 22 = 0 ; Solve for: "x" ;
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Let us factor the "left-hand side" of the equation:
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"x² + 9x − 22" ;
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What are the factors of "-22"" that add up to "positive 9" ?
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Let us list the factors of "-22" :
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-2, 11; → -2 + 11 = 9 ;
-11, 2; → -11 + 2 = -9 ;
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So we have: "-2" and "11" ;
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So; "x² + 9x − 22" ; factors into " (x−2)(x + 11)" ;
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We have: (x−2)(x + 11) = 0 ;

So: x − 2 = 0 ;

Add "2" to each side of the equation;

x − 2 + 2 = 0 + 2 ;

x = 2 ;
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x + 11 = 0 ;

Subtract "11" from each side of the equation;

x + 11 − 11 = 0 − 11 ;

x = -11 ;
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Answer: x = 2 ; -11 .
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