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In solving quadratic equation x^(2) + px...

In solving quadratic equation `x^(2) + px + q = 0 `, one student makes mistake only in the constant term obtains 4 and 3 as the roots. Another students makes a mistake only in the coefficient of x and finds - 5 and - 2 as the roots. Determine the correct equation

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To solve the problem, we need to determine the correct quadratic equation based on the information given about the mistakes made by two students. ### Step-by-Step Solution: 1. **Understanding the Problem**: We have a quadratic equation of the form \( x^2 + px + q = 0 \). - The first student finds the roots to be 4 and 3, but makes a mistake in the constant term \( q \). - The second student finds the roots to be -5 and -2, but makes a mistake in the coefficient of \( x \) (which is \( p \)). 2. **Using the First Student's Roots**: - The roots are 4 and 3. - The sum of the roots \( S_1 = 4 + 3 = 7 \). - The product of the roots \( P_1 = 4 \times 3 = 12 \). - According to Vieta's formulas, for the equation \( x^2 + px + q = 0 \): - The sum of the roots \( S = -p \) implies \( p = -7 \). - The product of the roots \( P = q \) implies \( q = 12 \). 3. **Using the Second Student's Roots**: - The roots are -5 and -2. - The sum of the roots \( S_2 = -5 + (-2) = -7 \). - The product of the roots \( P_2 = (-5) \times (-2) = 10 \). - According to Vieta's formulas: - The sum of the roots \( S = -p \) implies \( p = 7 \). - The product of the roots \( P = q \) implies \( q = 10 \). 4. **Identifying the Mistakes**: - The first student correctly calculated \( p \) but made a mistake in \( q \). So, \( p = -7 \) is correct. - The second student correctly calculated \( q \) but made a mistake in \( p \). So, \( q = 10 \) is correct. 5. **Forming the Correct Equation**: - The correct values for \( p \) and \( q \) are: - \( p = -7 \) - \( q = 10 \) - Therefore, the correct quadratic equation is: \[ x^2 - 7x + 10 = 0 \] ### Final Answer: The correct quadratic equation is: \[ x^2 - 7x + 10 = 0 \]
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