Q. Lea solves the equation below by first squaring both sides of the equation.3+2y=−yWhat extraneous solution does Lea obtain?y=
Perform Squaring: Now, let's perform the squaring on both sides.(3+2y)2=−y9+12y+4y2=−y
Move Terms: Next, we'll move all terms to one side to set the equation to zero.4y2+12y+y+9=04y2+13y+9=0
Solve Quadratic Equation: Now, we need to solve the quadratic equation for y. We can use the quadratic formula, y=2a−b±b2−4ac, where a=4, b=13, and c=9.
Find Solutions: Since the discriminant is positive, we have two real solutions. Let's find them using the quadratic formula.y=2×4−13±25y=8−13±5
Check Validity: Now, let's find the two solutions.First solution: y=(−13+5)/8y=−8/8y=−1Second solution: y=(−13−5)/8y=−18/8y=−2.25
Check Validity: Now, let's find the two solutions.First solution: y=(−13+5)/8y=−8/8y=−1Second solution: y=(−13−5)/8y=−18/8y=−2.25We have two potential solutions, y=−1 and y=−2.25. However, we need to check these solutions in the original equation to see if any of them is extraneous.Original equation: 3+2y=−y
Check Validity: Now, let's find the two solutions.First solution: y=(−13+5)/8y=−8/8y=−1Second solution: y=(−13−5)/8y=−18/8y=−2.25We have two potential solutions, y=−1 and y=−2.25. However, we need to check these solutions in the original equation to see if any of them is extraneous.Original equation: 3+2y=−yLet's substitute y=−1 into the original equation.y=−8/80y=−8/81y=−8/82This solution is valid.
Check Validity: Now, let's find the two solutions.First solution: y=(−13+5)/8y=−8/8y=−1Second solution: y=(−13−5)/8y=−18/8y=−2.25We have two potential solutions, y=−1 and y=−2.25. However, we need to check these solutions in the original equation to see if any of them is extraneous.Original equation: 3+2y=−yLet's substitute y=−1 into the original equation.y=−8/80y=−8/81y=−8/82This solution is valid.Now, let's substitute y=−2.25 into the original equation.y=−8/84y=−8/85y=−8/86This is not true, so y=−2.25 is an extraneous solution.
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