Chapter 13.6, Problem 15WE

To determine

To find:Slope and y-intercept of each line. Plot the y-intercept. Then using the slope, plot one more point. Finally graph the line.

Answer to Problem 15WE

The slope is $-4$ and the y-intercept is $0$ .

Explanation of Solution

Given information:Line: $y=-4x$ .

Concept Used:A line with the equation $y=mx+b$ has slope $m$ and $y\text{-intercept }b$ .

Calculation:

Comparing the line $y=-4x$ with equation $y=mx+b$ :

The slope of line, $m=-4$ and the $y\text{-intercept, }b=0$

Since, $y\text{-intercept is 0}$

So, one point is $(x_1,y_1)\equiv (0,0)$

For one more point, using $m=\frac{y_2-y_1}{x_2-x_1}=-4$ :

Let taking $x_2=1$ , then

  $\begin{array}{l}\frac{y_2-0}{1-0}=-4\\ \Rightarrow y_2=-4\end{array}$

So, second point is $(x_2,y_2)\equiv (1,-4)$

Hence, the slope is $-4$ and the y-intercept is $0$ .

Graph: