My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Thanks Tree1Thanks
  • 1 Post By skipjack
Reply
 
LinkBack Thread Tools Display Modes
May 5th, 2017, 09:28 PM   #1
Member
 
Joined: Jan 2017
From: US

Posts: 86
Thanks: 5

Y Varies Directly With X

Suppose y varies directly with x. If y = negative-4 when x = 1/2, what is the value of y when x =2/3?

So, how would I set this up compared to how I would set it up if y was inversely related to x?
Indigo28 is offline  
 
May 6th, 2017, 12:54 AM   #2
Global Moderator
 
Joined: Dec 2006

Posts: 17,482
Thanks: 1314

"y varies directly with x" means that y = kx, where k is a constant. Does that help?
Thanks from Indigo28
skipjack is offline  
May 6th, 2017, 11:03 PM   #3
Member
 
Joined: Jan 2017
From: US

Posts: 86
Thanks: 5

Quote:
Originally Posted by skipjack View Post
"y varies directly with x" means that y = kx, where k is a constant. Does that help?
Yes that definitely helps! I think I had the formulas mixed up.

So would it be:

-4 = k*1/2

k= -2

x= 2/3 k= -2

2/3*-2= -1.3.

So if x= 2/3, does y= -1 3/10?
Indigo28 is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
directly, varies



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
apples are not counted directly estim Elementary Math 3 March 28th, 2015 06:12 AM
use definition to find laplace transform directly mbradar2 Calculus 6 December 12th, 2010 05:45 PM
cube and directly varies chicagobearsconvulse Calculus 1 April 28th, 2009 05:53 AM





Copyright © 2017 My Math Forum. All rights reserved.