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#1 2015-08-12 20:30:23

Mystogan
Member
Registered: 2015-08-12
Posts: 12

Coordinate Geometry

This question appeared in my test and I wasn't able to solve it. I would be grateful to you if you could provide me with details on how to solve it.

Find the value of b if the lines x-2y+3=0, 3x-y=1 and bx-y+1=0 are concurrent.

(A) 1
(B) 1/2
(C) 3/2
(D) 5/2

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#2 2015-08-12 20:42:32

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Coordinate Geometry

Hi;

A) 1

Solve the 3 equations simultaneously.

From the first equation you have x = 2y - 3. Substitute that into the 2nd and 3rd equation.

Solve for y in the first equation and you get y = 2. Now solve for b in the second equation.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2015-08-12 22:46:51

Mystogan
Member
Registered: 2015-08-12
Posts: 12

Re: Coordinate Geometry

Thank you for the help, bobbym.

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#4 2015-08-13 04:39:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Coordinate Geometry

Hi;

You are welcome and welcome to the forum.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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