# Thread: equation of the line AB

1. ## equation of the line AB

hi,

i need to find the equation of the line AB from A(2,0) B(3,1)

for this would i do:

AB=(square root) 1^2 + 1^2= (square root)2?

is this correct? if not where am i going wrong?

2. ## Re: equation of the line AB

The equation of a line refers to an equation in x and y which all points on that line satisfy. You have tried to find out the length of the line-segment AB which is not required. The following link should help.

Linear equation - Wikipedia, the free encyclopedia

3. ## Re: equation of the line AB

thanks!

so would i do:
0=2m+c
1=3m+c

-1=-1

m=1
1=3+c 1/3=0.3
c=0.3

Y=1x+0.3???

4. ## Re: equation of the line AB

would that be correct?

5. ## Re: equation of the line AB

Originally Posted by andyboy179
thanks!

so would i do:
0=2m+c
1=3m+c

-1=-1

m=1

1=3+c
Correct.

1/3=0.3
c=0.3

Y=1x+0.3???
There is a slight error in this. How do you solve 1 = 3 + c ?

6. ## Re: equation of the line AB

i did, 1/3=0.3

7. ## Re: equation of the line AB

That is not how it is done. In an equation you perform the same operation on both sides. For example you can subtract some quantity, or divide both sides by a non-zero number. Which of the above would you do to get only c in a single side of 1 = 3 + c ?

8. ## Re: equation of the line AB

could i -1 from both sides to make c=2?

9. ## Re: equation of the line AB

That way you will get 0 = 2 + c. What is the next step?

10. ## Re: equation of the line AB

-2 from each side so c=-2 and the final answer would be y=1x-2???

11. ## Re: equation of the line AB

Originally Posted by andyboy179
-2 from each side so c=-2 and the final answer would be y=1x-2???
Absolutely !

12. ## Re: equation of the line AB

thanks alot mate!!