Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

Published by Pearson
ISBN 10: 0-32193-104-1
ISBN 13: 978-0-32193-104-7

Chapter F - Foundations: A Prelude to Functions - Section F.3 Lines - F.3 Assess Your Understanding - Page 30: 44



Work Step by Step

The equation of a line in the point-slope form is the following: $y-y_1=m(x-x_1)$, where $m$ is the slope and the point $(x_1,y_1)$ is on the graph. In order to determine the equation of a line, we have to calculate the slope. For this, we can use the rule, that the product of the slopes of two perpendicular lines equals $-1$. Here, a perpendicular line is $y=-x$. In this form, the slope can be seen as the coefficient of $x$, which is $-1$. Therefore our line's slope $m$ can be calculated as: $m\times(-1)=-1$ $m=\dfrac{-1}{-1}=1$ Therefore, using the point $(-1, 1)$ and the slope $1$, the equation can be written as: $y-1=1(x-(-1))$ $y-1=x+1\\ y=x+1+1\\ y=x+2$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.