Question

There goes the chart on the left for the question on the right

Answer 1

Step 1

State the equation of line that can be used to model the values on the table.

`y-y_1=\text{ }(y_2-y_1)/(x_2-x_1)(x-x_1)`

Where

`\begin{gathered} y_1=\text{ 8} \\ y_2=\text{ 12} \\ x_1=2 \\ x_2=4 \end{gathered}`

Step 2

Put in the value and find the equation of the line.

`\begin{gathered} y-8=(12-8)/(4-2)(x-2) \\ y-8=(4)/(2)(x-2) \\ y-8=2x-2(2) \\ y=2x-4+8 \\ y=2x+4 \\ \end{gathered}`

Step 3

Given an output of 120feet, find the input

`\begin{gathered} 120\text{ = 2}x+4 \\ 120-4=2x \\ 2x=116 \\ (2x)/(2)=(116)/(2) \\ x=58\text{ seconds} \end{gathered}`

Hence, the input is 58seconds.