A student expanded \((x+5)(x-2)\) as \(x^2+3x-10\). What is the correct evaluation of the student's answer?
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Answer and explanation
Correct answer: उत्तर सही है, क्योंकि मध्य पद \(5x-2x=3x\) है।
Using distribution, \((x+5)(x-2)=x^2-2x+5x-10=x^2+3x-10\). Thus the student is correct. Exam tip: add the two cross-products carefully and check their signs before combining like terms.
Frequently asked questions
What is the correct answer to this question?
उत्तर सही है, क्योंकि मध्य पद \(5x-2x=3x\) है।
Why is this the correct answer?
Using distribution, \((x+5)(x-2)=x^2-2x+5x-10=x^2+3x-10\). Thus the student is correct. Exam tip: add the two cross-products carefully and check their signs before combining like terms.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Exploring Algebraic Identities. Topic: Quadratic expressions.
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