IDNLearn.com is the place where your questions are met with thoughtful and precise answers. Get accurate and detailed answers to your questions from our knowledgeable and dedicated community members.

Gerri purchases a coupon book with discounts for her favorite coffee shop. Every coupon for the coffee shop offers the same discount. The table shows her total savings, [tex]$y$[/tex], based on the number of coupons, [tex]$x$[/tex], used from the book.

Coffee Shop Coupon Savings

[tex]\[
\begin{tabular}{|c|c|}
\hline
$x$ & $y$ \\
\hline
0 & -20 \\
\hline
5 & -10 \\
\hline
10 & 0 \\
\hline
15 & 10 \\
\hline
20 & 20 \\
\hline
\end{tabular}
\][/tex]

What are the slope and [tex]$y$[/tex]-intercept of the line represented by the points shown in the table?

A. slope: [tex]$2$[/tex], [tex]$y$[/tex]-intercept: -20
B. slope: [tex]$2$[/tex], [tex]$y$[/tex]-intercept: 10
C. slope: [tex]$5$[/tex], [tex]$y$[/tex]-intercept: -20
D. slope: [tex]$5$[/tex], [tex]$y$[/tex]-intercept: 10


Sagot :

To find the slope and [tex]\( y \)[/tex]-intercept of the line represented by the points in the table, we need to follow these steps:

### Step 1: Understanding the Table
The given table shows the relationship between the number of coupons [tex]\( x \)[/tex] and the total savings [tex]\( y \)[/tex]:

[tex]\[ \begin{array}{|c|c|} \hline x & y \\ \hline 0 & -20 \\ \hline 5 & -10 \\ \hline 10 & 0 \\ \hline 15 & 10 \\ \hline 20 & 20 \\ \hline \end{array} \][/tex]

### Step 2: Calculate the Slope (m)
The slope [tex]\( m \)[/tex] of a line through two points [tex]\((x_1, y_1)\)[/tex] and [tex]\((x_2, y_2)\)[/tex] is calculated using the formula:

[tex]\[ m = \frac{y_2 - y_1}{x_2 - x_1} \][/tex]

We can choose any two points from the table for this calculation. Let's take the points (0, -20) and (5, -10).

Here, [tex]\( x_1 = 0 \)[/tex], [tex]\( y_1 = -20 \)[/tex], [tex]\( x_2 = 5 \)[/tex], and [tex]\( y_2 = -10 \)[/tex].

Using the formula:
[tex]\[ m = \frac{-10 - (-20)}{5 - 0} = \frac{-10 + 20}{5} = \frac{10}{5} = 2 \][/tex]

So, the slope [tex]\( m \)[/tex] is [tex]\( 2 \)[/tex].

### Step 3: Determine the y-intercept (b)
The [tex]\( y \)[/tex]-intercept [tex]\( b \)[/tex] is the point where the line crosses the [tex]\( y \)[/tex]-axis. This occurs when [tex]\( x = 0 \)[/tex].

From the table, when [tex]\( x = 0 \)[/tex], [tex]\( y = -20 \)[/tex]. Therefore, the [tex]\( y \)[/tex]-intercept [tex]\( b \)[/tex] is [tex]\( -20 \)[/tex].

### Final Answer
The slope and [tex]\( y \)[/tex]-intercept of the line represented by the points shown in the table are:
[tex]\[ \text{slope: } 2, \ y\text{-intercept: } -20 \][/tex]

This means the correct answer is:
[tex]\[ \text{slope: } 2, \ y\text{-intercept: } -20 \][/tex]