Which rule has initial value (33) and growth rate (4)?

Correct answer: \(y=33+4x\)

A linear rule has the form \(y=a+bx\), where \(a\) is the initial value and \(b\) is the growth rate. In \(y=33+4x\), the constant term is \(33\) and the coefficient of \(x\) is \(+4\), so it is the correct rule. Although \(y=33-4x\) starts at 33, its rate is \(-4\), which represents decay rather than growth. Exam tip: put \(x=0\) to identify the initial value, and check the coefficient of \(x\) for the growth or decay rate.