Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 30 Nov 2015, 11:20

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# slope 3

Author Message
Manager
Joined: 16 Apr 2009
Posts: 243
Schools: Ross
Followers: 2

Kudos [?]: 53 [0], given: 10

slope 3 [#permalink]  14 Jul 2009, 13:09
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

The x-intercept of a line passing through points (5,-2) and (6,9) is _________________________
[Reveal] Spoiler:
57/11

_________________

Keep trying no matter how hard it seems, it will get easier.

Senior Manager
Joined: 25 Mar 2009
Posts: 305
Followers: 7

Kudos [?]: 136 [0], given: 6

Re: slope 3 [#permalink]  14 Jul 2009, 13:16
You have to use a system of 2 equations. Plug in your given points into the formula for a line: y=mx+b

A: -2=m(5)+b
B: 9=m(6)+b

Subtract the bottom from the top:
-11 = -m
m = 11

Plug back into a to find the full equation:
A: -2=11(5)+b
b=-57

x-int. is where the line crosses the x-axis which means y=0. Plug this in:
y=11x-57
0=11x-57
x=57/11
Manager
Joined: 07 Apr 2009
Posts: 145
Followers: 1

Kudos [?]: 9 [0], given: 3

Re: slope 3 [#permalink]  15 Jul 2009, 07:07
given 2 points there is a direct eqn for a line

$$y-y2 = y2-y1/x2-x1 (x-x1)$$

using this , you get the eqn y+2 = 11(x-5)

for x-interecept you put y=0 and you get x = 57/11
Senior Manager
Joined: 25 Mar 2009
Posts: 305
Followers: 7

Kudos [?]: 136 [0], given: 6

Re: slope 3 [#permalink]  15 Jul 2009, 08:42
skpMatcha wrote:
given 2 points there is a direct eqn for a line

$$y-y2 = y2-y1/x2-x1 (x-x1)$$

using this , you get the eqn y+2 = 11(x-5)

for x-interecept you put y=0 and you get x = 57/11

I think your equation is wrong. I tried plugging in numbers and didn't get the correct equation. I believe the left side of the equation should be y - y1, not y - y2. Please confirm.
Manager
Joined: 07 Apr 2009
Posts: 145
Followers: 1

Kudos [?]: 9 [0], given: 3

Re: slope 3 [#permalink]  15 Jul 2009, 09:00
you are correct, you can use either of the points here but you need to stick with one point and use x & y coordinates of that point !

thanks for the correction!
Manager
Joined: 07 Apr 2009
Posts: 145
Followers: 1

Kudos [?]: 9 [0], given: 3

Re: slope 3 [#permalink]  15 Jul 2009, 09:07
$$y-y2= y2-y1/x2-x1(x-x2)$$

or

$$y-y1= y2-y1/x2-x1(x-x1)$$
Manager
Joined: 16 Apr 2009
Posts: 243
Schools: Ross
Followers: 2

Kudos [?]: 53 [0], given: 10

Re: slope 3 [#permalink]  15 Jul 2009, 17:50
Thanks for the replies.
_________________

Keep trying no matter how hard it seems, it will get easier.

Re: slope 3   [#permalink] 15 Jul 2009, 17:50
Display posts from previous: Sort by

# slope 3

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.