All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
A meeting point (Posted on 2018-01-07) Difficulty: 3 of 5
The lines with equations:
y = x + 1,
y = mx − 1,
& y = −4x + 2m
pass through the same point.

Determine all possible values for m.

See The Solution Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution solution | Comment 1 of 2
y = x+1
y = mx - 1
x+1 = mx - 1

(m-1)x = 2

x = 2/(m-1)
y = 2/(m-1) + 1

2/(m-1) + 1 = -8/(m-1) + 2m

2 + m - 1 = -8 + 2m(m-1)

2m^2 - 2m - 8 - 2 - m + 1 = 0

2m^2 - 3m - 9 = 0

m = (3 +/- sqrt(9 + 72)) / 4

m = (3 +/- sqrt(81)) / 4

m = (3 +/- 9) / 4

m = 3 or -1.5

  Posted by Charlie on 2018-01-07 12:24:25
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (2)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2018 by Animus Pactum Consulting. All rights reserved. Privacy Information