Chapter 9.2, Problem 12GP

a.

To determine

To find: the $x$ -and $y$ -intercepts and then graph the equation

Answer to Problem 12GP

The $x$ -intercepts is $-2$ , and $y$ -intercepts is $5$ .

Explanation of Solution

Given information:

Y walked her dog 5 miles today and plans to walk her dog 2.5 miles every day from now on. The total number of miles walked $y$ can be represented by $y=2.5+5$ , where $x$ is the number days walked after today.

Calculation:

To find the $x$ -intercept,

  $\begin{array}{l}\text{Let }y=0\\ y=2.5x+5\\ 0=2.5x+5\\ 2.5x=-5\\ x=\frac{-5}{2.5}\\ x=-2\end{array}$

To find the $y$ -intercept,

  $\begin{array}{l}\text{Let x}=0\\ y=2.5x+5\\ y=2.5\left(0\right)+5\\ y=5\end{array}$

Therefore, the graph obtained as

  

Hence, the $x$ -intercepts is $-2$ , and $y$ -intercepts is $5$ .

b.

To determine

To explain:

Answer to Problem 12GP

The $x$ - intercept is meaningless and y- intercept means the initial 5 miles she walked today.

Explanation of Solution

Given information:

Y walked her dog 5 miles today and plans to walk her dog 2.5 miles every day from now on. The total number of miles walked $y$ can be represented by $y=2.5+5$ , where $x$ is the number days walked after today.

The $x$ - intercepts is meaningless, as Y cannot walk her dog for negative days

The y- intercept means the initial 5 miles she walked today

Hence, the $x$ - intercept is meaningless and y- intercept means the initial 5 miles she walked today.