Linear Functions help

[Christiano]

How do you find the equation of a line joining two points (-2,3)(3,4) that form one side of a square?

And

What is the equation of the line that passes through the midpoint of the interval AB where A is the point (-3,11) and B is the point (7,-7), making an angle of 135 degrees with the positive direction of the x-axis

Mind Blank!

[monokekie]

the first question:

I will find the gradient first, through rise/run, which is (4-3)/(3-[-2]) , which is 1/5

then pick just one point, either (-2,3) or (3,4) to find the equation,
let's pick (3,4), so 3= X1, and 4 =Y1
now we apply the formula, y-y1=x-x1 (i hope i m correct here)
so we get y-4=x-3 , re-arrange it,
y=x+1
hopefully the above equation is what your BOB says

someone else might be able to explain better though, lol

[GerrySly]

Now using the equation of a line

Then just do a quick test...

and

[monokekie]

*crawls into a hole*

[simonhu81292]

*crawls into a hole*

no need to ...
i'll support you!!!
 

[Christiano]

Thanks peeps. Do I do the same thing with the second question? What do I do with the angle ?

[Christiano]

How does the y-3 = 1/5(x+2) turn into (x+17)

[simonhu81292]

yeah... once you got your midpoint .. which is 2,2
your gradient can only be pos 1 or neg 1...
therefore tan(angle)=O/A
so your gradient would be neg 1 ..
and find the equation like what kekie did
your answer should be y=-x+4
 

[simonhu81292]

How does the y-3 = 1/5(x+2) turn into (x+17)

you just expand it and you will get the same answer