By elimination, what is (x) after adding (3x+2y=20) and (3x-2y=4)?
Answer and explanation
Correct answer: \(x=4\)
Adding the two equations gives \((3x+2y)+(3x-2y)=20+4\). The \(+2y\) and \(-2y\) terms cancel, so \(6x=24\). Hence, \(x=4\). \(x=6\) may seem close, but it results from solving \(6x=24\) incorrectly. Exam tip: in elimination, first check whether the coefficients of one variable are opposites.
Frequently asked questions
What is the correct answer to this question?
\(x=4\)
Why is this the correct answer?
Adding the two equations gives \((3x+2y)+(3x-2y)=20+4\). The \(+2y\) and \(-2y\) terms cancel, so \(6x=24\). Hence, \(x=4\). \(x=6\) may seem close, but it results from solving \(6x=24\) incorrectly. Exam tip: in elimination, first check whether the coefficients of one variable are opposites.
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..
