Maths Question

SligoBrewer

Right. Bitta help here please.

Co-Ordinate Geometry of the Line.

L is the line x= t/t+1, y=1/t+1

express L in the form ax+by+c=0

It's for a 5th year summer test tomorrow morning. Just revising now.

Cheers,
Brewer

Daysha

Express t in terms of x and t in terms of y, and let them equal each other.

SligoBrewer

deise59 wrote: »

Express t in terms of x and t in terms of y, and let them equal each other.

Oh I do know that, I was having trouble getting t on its own though.:o

littlneutralone

Ooh I just revised this today.

x = t/(t+1)

cross multiply: t=xt + x
t - xt = x
t(1-x) = x
t = x/(1-x)

y = 1/(t+1)
y(t+1)=1
ty + y =1
ty = 1-y
t= (1-y)/y

equate the values for t

x/(1-x) = (1-y)/y

xy = (1-x)(1-y)
xy = 1 - y - x + xy
0 = 1 - y - x
x + y = 1

better have someone confirm it though, I suck at maths :pac:

SligoBrewer

Your a star thanks!:)

littlneutralone

Wow me do good? Good luck.

JC 2K3

You could just add the two equations:

x = t/(t+1)
y = 1/(t+1)

x + y = (t+1)/(t+1)
x + y = 1