# Lesson: Graphing Lines

## Comment on Graphing Lines

### Pls help with the following

Pls help with the following question: https://gmatclub.com/forum/on-the-graph-above-when-x-1-2-y-2-and-when-x-1-y-136560.html (Question No. 8 from OG 2017) ### Is this why we say that a

Is this why we say that a straight line is made of an infinite number of dots? ### You bet! The same applies to

You bet! The same applies to the number line.

Cheers,
Brent

### Hi Brent,

Hi Brent,
Grateful if you could provide me with your approach to solve this problem.
Thanks

In the xy-coordinate system, if (a, b) and (a+3, b+k) are two points on the line defined by the equation x = 3y - 7, then k =

A) 9
B) 3
C) 7/3
D) 1
E) 1/3 Here's my full solution: https://gmatclub.com/forum/in-the-xy-coordinate-system-if-a-b-and-a-3-b-...

Cheers,
Brent

### Hi Brent,

Hi Brent,
Just checking for this question: I found it easier and faster to answer using this approach, is it sound?

Question:
In the xy-coordinate system, if (a, b) and (a+3, b+k) are two points on the line defined by the equation x = 3y - 7, then k =
_________
All i did was find the x intercept and substituted to get the why intercept.

So...
x= 3(0) -7
x=-7

(-7+3, 0+k)

-4=3y-7
y=1

(a+3,b+k)
(-7+3, 0+1)

therefore k=1

I think its a right approach that i hope to use in future, will it work or did I just get lucky? 