If (p(x)=5x-4), what is the value of (p(4)-p(2))?
Answer and explanation
Correct answer: 10
Given \(p(x)=5x-4\), we get \(p(4)=5\times4-4=16\) and \(p(2)=5\times2-4=6\). Hence, \(p(4)-p(2)=16-6=10\), so option D is correct. Option B can result from handling the constant term \(-4\) incorrectly; evaluate the polynomial completely at both inputs before subtracting. Exam tip: find each function value separately, then take their difference.
Frequently asked questions
What is the correct answer to this question?
10
Why is this the correct answer?
Given \(p(x)=5x-4\), we get \(p(4)=5\times4-4=16\) and \(p(2)=5\times2-4=6\). Hence, \(p(4)-p(2)=16-6=10\), so option D is correct. Option B can result from handling the constant term \(-4\) incorrectly; evaluate the polynomial completely at both inputs before subtracting. Exam tip: find each function value separately, then take their difference.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Introduction to Polynomials. Topic: Linear polynomials.
