Q. Tessa solves the equation below by first squaring both sides of the equation.x2−3x−6=x−1What extraneous solution does Tessa obtain?x=
Eliminate square root: Square both sides of the equation to eliminate the square root.x2−3x−6=x−1(x2−3x−6)2=(x−1)2x2−3x−6=(x−1)(x−1)
Expand right side: Expand the right side of the equation. x2−3x−6=x2−2x+1
Simplify equation: Subtract x2 from both sides to simplify the equation.x2−x2−3x−6=x2−x2−2x+1−3x−6=−2x+1
Isolate x term: Add 2x to both sides to isolate the x term on one side.−3x+2x−6=−2x+2x+1−x−6=1
Solve for x: Add 6 to both sides to solve for x.−x−6+6=1+6−x=7
Check solution: Multiply both sides by −1 to find the value of x.−x×−1=7×−1x=−7
Check solution: Multiply both sides by −1 to find the value of x. −x×−1=7×−1 x=−7 Check the solution in the original equation to see if it is an extraneous solution. (−7)2−3(−7)−6=−7−1 49+21−6=−8 64=−8 8=−8 The solution x=−7 does not satisfy the original equation, so it is an extraneous solution.
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