If (P(t)=a+5t) and (P(0)=18), what is (a)?
Advertisement
Answer and explanation
Correct answer: 18
Given \(P(t)=a+5t\), substitute \(t=0\): \(P(0)=a+5(0)=a\). Since \(P(0)=18\), we get \(a=18\). The number 5 is the rate of increase, not the initial value. Exam tip: in a linear expression \(a+bt\), putting \(t=0\) gives the initial value \(a\).
Frequently asked questions
What is the correct answer to this question?
18
Why is this the correct answer?
Given \(P(t)=a+5t\), substitute \(t=0\): \(P(0)=a+5(0)=a\). Since \(P(0)=18\), we get \(a=18\). The number 5 is the rate of increase, not the initial value. Exam tip: in a linear expression \(a+bt\), putting \(t=0\) gives the initial value \(a\).
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Introduction to Polynomials. Topic: Linear growth and decay.
Advertisement