If (x=7,\ y=4) is a solution of (2x+my=34), what will be the value of (m)?
Answer and explanation
Correct answer: \(m=5\)
The given solution \(x=7,\ y=4\) must satisfy \(2x+my=34\). Substituting gives \(2(7)+m(4)=34\), or \(14+4m=34\). Hence, \(4m=20\) and \(m=5\). If \(m=4\), the left-hand side becomes \(30\), not \(34\). Exam tip: To find an unknown parameter from a given solution, substitute the values directly into the equation.
Frequently asked questions
What is the correct answer to this question?
\(m=5\)
Why is this the correct answer?
The given solution \(x=7,\ y=4\) must satisfy \(2x+my=34\). Substituting gives \(2(7)+m(4)=34\), or \(14+4m=34\). Hence, \(4m=20\) and \(m=5\). If \(m=4\), the left-hand side becomes \(30\), not \(34\). Exam tip: To find an unknown parameter from a given solution, substitute the values directly into the equation.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Pair of Linear Equations in Two Variables. Topic: Algebraic methods: Substitution method and Elimination method..
