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Maths Challenge! (1 Viewer)

Real Madrid

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Find the equation of the locus of a point that moves so that it is equidistant from the line

4x-3x+2=0
3x+4y-7=0

Show working
 

Timothy.Siu

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Find the equation of the locus of a point that moves so that it is equidistant from the line

4x-3x+2=0
3x+4y-7=0

let P be a point (x,y)
perpendicular distance from both the lines is

D= (4x-3y+2)/root(x^2+y^2)

D= (3x+4y-7)/root(x^2+y^2)

4x-3y+2=3x+4y-7
x-7y+9=0 dunno if thats correct
 

lolokay

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^ you forgot the absolute values
it would be:
4x-3y+2=3x+4y-7
x-7y+9=0

or
4x - 3y + 2 = -(3x + 4y - 7)
7x + y - 5 = 0
 
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Timothy.Siu said:
Find the equation of the locus of a point that moves so that it is equidistant from the line

4x-3x+2=0
3x+4y-7=0

let P be a point (x,y)
perpendicular distance from both the lines is

D= (4x-3y+2)/root(x^2+y^2)

D= (3x+4y-7)/root(x^2+y^2)

4x-3y+2=3x+4y-7
x-7y+9=0 dunno if thats correct
right idea, just got the formula wrong
but because of the nature of the question you still got the correct answer

shoulde be |4x-3y+2|/5=|3x+4y-7|/5 ( 5=sqr(3^2+4^2))

so 4x-3y+2=3x+4y-7 or 4x-3y+2 = -3x-4y+7
x-7y+9=0 or 7x+y-5=0

and im not sure why you call this a maths challenge??
sure oyu just couldnt do it?
 
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shaon0

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Real Madrid said:
Find the equation of the locus of a point that moves so that it is equidistant from the line

4x-3x+2=0
3x+4y-7=0

Show working
can you stop naming all your threads with challenge or some other superlative when the question is not very hard or a challenge.
Thanks
 

lyounamu

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shaon0 said:
can you stop naming all your threads with challenge or some other superlative when the question is not very hard or a challenge.
Thanks
QFT
 

5647382910

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tacogym27101990 said:
right idea, just got the formula wrong
but because of the nature of the question you still got the correct answer

shoulde be |4x-3y+2|/5=|3x+4y-7|/5 ( 5=sqr(3^2+4^2))

so 4x-3y+2=3x+4y-7 or 4x-3y+2 = -3x-4y+1
x-7y+9=0 or 7x+y-5=0

and im not sure why you call this a maths challenge??
sure oyu just couldnt do it?
wiht ur second answer how come |3x + 4y -7| = -3x -4y + 1 (im talking about the -7 changing to 1)? and also with the absolute values why did you do both negative and positive for the RHS and not the left (|4x - 3y + 2|)?
 

lolokay

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5647382910 said:
wiht ur second answer how come |3x + 4y -7| = -3x -4y + 1 (im talking about the -7 changing to 1)? and also with the absolute values why did you do both negative and positive for the RHS and not the left (|4x - 3y + 2|)?
probs a typo

and because taking the negative of both sides is the same of having the positive of both sides, and taking the negative of only one side is the same as taking the negative of only the other (multiply each side by -1)
 

Timothy.Siu

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5647382910 said:
? and also with the absolute values why did you do both negative and positive for the RHS and not the left (|4x - 3y + 2|)?
because u dont need to, its the same
e.g. |x+2|=|2x-1|
u only need to do 2 cases not 4
as -(x+2)=2x-1 is the same as x+2=-(2x-1)
 

5647382910

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Timothy.Siu said:
because u dont need to, its the same
e.g. |x+2|=|2x-1|
u only need to do 2 cases not 4
as -(x+2)=2x-1 is the same as x+2=-(2x-1)
ok i see.. thanks
 

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