Intervals On Number Line

Intervals On Number Line

Postby nycmath » Thu Aug 13, 2026 11:26 am

Precalculus
David Cohen
Edition 3
Chapter 1, Section 1.2

Show intervals on a number line.

58. | x - 1 | < 4

62. | x + 5 | > or = 2
nycmath
 
Posts: 1952
Joined: Mon Aug 10, 2026 10:40 pm
Reputation: 76

Re: Intervals On Number Line

Postby Eigenvalue » Thu Aug 13, 2026 7:08 pm

58. |x-1|<4 means that the distance from x to 1 is less than 4
x-1>-4 and x-1<4
-4<x-1<4
-3<x<5

62. |x+5|[tex]\ge[/tex]2 means that the distance from x to negative 5 is greater than or equal to 2
x+5[tex]\ge[/tex]2 or x+5[tex]\le[/tex]-2
x[tex]\ge[/tex]-3 or x[tex]\le[/tex]-7

Eigenvalue
 
Posts: 1100
Joined: Mon Aug 10, 2026 10:38 pm
Reputation: 397

Re: Intervals On Number Line

Postby Eigenvalue » Thu Aug 13, 2026 7:19 pm

Generalized formulas:
|x-h|>c
x-h>c or x-h<-c
x>h+c or x<-(h+k)

|x-h|<c
x-h>-c and x-h<c
h-c<x<h+c

Eigenvalue
 
Posts: 1100
Joined: Mon Aug 10, 2026 10:38 pm
Reputation: 397

Re: Intervals On Number Line

Postby nycmath » Thu Aug 13, 2026 7:22 pm

Eigenvalue wrote:58. |x-1|<4 means that the distance from x to 1 is less than 4
x-1>-4 and x-1<4
-4<x-1<4
-3<x<5

62. |x+5|[tex]\ge[/tex]2 means that the distance from x to negative 5 is greater than or equal to 2
x+5[tex]\ge[/tex]2 or x+5[tex]\le[/tex]-2
x[tex]\ge[/tex]-3 or x[tex]\le[/tex]-7


Thank you for your effort. Where's the number line?

nycmath
 
Posts: 1952
Joined: Mon Aug 10, 2026 10:40 pm
Reputation: 76

Re: Intervals On Number Line

Postby Eigenvalue » Thu Aug 13, 2026 7:41 pm

The website is somehow not letting me post pictures from my phone. I will try it with my laptop

Eigenvalue
 
Posts: 1100
Joined: Mon Aug 10, 2026 10:38 pm
Reputation: 397

Re: Intervals On Number Line

Postby nycmath » Fri Aug 14, 2026 4:12 am

Eigenvalue wrote:The website is somehow not letting me post pictures from my phone. I will try it with my laptop


The number line picture requested is not only for me but for members to see and learn.
nycmath
 
Posts: 1952
Joined: Mon Aug 10, 2026 10:40 pm
Reputation: 76


Return to College Math



Who is online

Users browsing this forum: No registered users and 1 guest