Q. Rania solves the equation below by first squaring both sides of the equation.−5=3x−7What extraneous solution does Rania obtain?x=
Square both sides: Square both sides of the equation to eliminate the square root.−5=3x−7(−5)2=(3x−7)225=3x−7
Add 7 to isolate x: Add 7 to both sides of the equation to isolate the term with x.25+7=3x−7+732=3x
Divide by 3 to solve for x: Divide both sides by 3 to solve for x.332=33xx=332
Check the solution: Check the solution by substituting x back into the original equation.−5=3(332)−7−5=32−7−5=25−5=5 or −5=−5The original equation states −5=3x−7, so the square root should only yield a positive result, meaning −5=5 is not possible. Therefore, x=332 is an extraneous solution.
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