Which rule has initial value (210) and decrease of (14) per step?
Answer and explanation
Correct answer: \(y=210-14x\)
A linear rule has the form \(y=a+bx\), where \(a\) is the initial value and \(b\) is the change per step. Here, the initial value is \(210\), and the value decreases by \(14\) each step, so \(b=-14\). Therefore, the rule is \(y=210-14x\). Option A represents an increase, not a decrease. Exam tip: Words such as “decrease” or “decay” indicate a negative coefficient of \(x\).
Frequently asked questions
What is the correct answer to this question?
\(y=210-14x\)
Why is this the correct answer?
A linear rule has the form \(y=a+bx\), where \(a\) is the initial value and \(b\) is the change per step. Here, the initial value is \(210\), and the value decreases by \(14\) each step, so \(b=-14\). Therefore, the rule is \(y=210-14x\). Option A represents an increase, not a decrease. Exam tip: Words such as “decrease” or “decay” indicate a negative coefficient of \(x\).
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Introduction to Polynomials. Topic: Linear growth and decay.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
