Chapter 13.2, Problem 1WE

a.

To determine

To find the line with positive slope

Answer to Problem 1WE

The lines $n\text{ and }y$ have positive slope.

Explanation of Solution

Given:

Below is the figuregiven

  

Calculation:

Since, slope is the ratio of y-intercept to the x-intercept of a line

  $\text{slope}=\frac{y-\text{intercept}}{x-\text{intercept}}$

From the given diagram , it is clear that $y-\text{intercept}$ and $x-\text{intercept}$ of line named $n\text{ and }y$ are positive.

Therefore the lines $n\text{ and }y$ have positive slope.

b.

To determine

To find the line with negative slope

Answer to Problem 1WE

The line $k$ have negative slope.

Explanation of Solution

Given:

Below is the figuregiven

  

Calculation:

Since, slope is the ratio of y-intercept to the x-intercept of a line

  $\text{slope}=\frac{y-\text{intercept}}{x-\text{intercept}}$

From the given diagram , it is clear that $y-\text{intercept}$ of line named $k$ is positive while its $x-\text{intercept}$ is negative.

Therefore the line $k$ have negative slope.

c.

To determine

To find the line with zero slope

Answer to Problem 1WE

The slope of line $l$ is zero.

Explanation of Solution

Given:

Below is the figure given

  

Calculation:

From the given diagram , it is clear that the line $X$ is making an angle $0^{°}$ with $x-\text{axis}$

  $\text{slope}=\tan \theta =\tan 0^{°}=0$

Therefore, the slope of line $l$ is zero.

d.

To determine

To find the line with undefinedslope

Answer to Problem 1WE

The slope of line $X$ is undefined

Explanation of Solution

Given:

Below is the figure given

  

Calculation:

From the given diagram , it is clear that the line $X$ is making an angle ${90}^{°}$ in anticlockwise direction with positive $x-\text{axis}$

  $\text{slope}=\tan \theta =\tan {90}^{°}=\text{undefined}$

Therefore, the slope of line $X$ is undefined.