If the roots of the equation \(x^2+vx+28=0\) are \(-4\) and \(-7\), what is the value of \(v\)?
Answer and explanation
Correct answer: 11
For the quadratic equation \(x^2+vx+28=0\), the sum of the roots is \(-v\). The given roots have sum \(-4+(-7)=-11\). Hence, \(-v=-11\), so \(v=11\). Option \(-11\) is the sum of the roots, not the value of \(v\). Exam tip: For \(ax^2+bx+c=0\), the sum of roots is \(-b/a\).
Frequently asked questions
What is the correct answer to this question?
11
Why is this the correct answer?
For the quadratic equation \(x^2+vx+28=0\), the sum of the roots is \(-v\). The given roots have sum \(-4+(-7)=-11\). Hence, \(-v=-11\), so \(v=11\). Option \(-11\) is the sum of the roots, not the value of \(v\). Exam tip: For \(ax^2+bx+c=0\), the sum of roots is \(-b/a\).
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Quadratic Equations. Topic: Introduction to Quadratic Equations.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
