##### Intersecting Lines; Equations of Lines

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A pair of lines intersect at point (-3,4). Which pair of equations represents these Lines?

a) 2x + 3y = 6 & y = x - 7

b) 2x + 3y = 6 & y =-3x + 4

c) 2x + 3y = 6 & y= -5/3x - 1

d) 2x + 3y = 6 & y= 4/3x + 4

Apr 7th, 2015

Option C

2x+3y=6               (1)

y = -5/3 * x -1

Multiplying by 3 and transposing x to the left side,

5x+3y = -3            (2)

2x+3y =6              (1)

5x+3y = -3            (2)

Subtracting 2 from 1

-3x= 9

x=-3

-6+3y=6

3y =6+6=12

y =4

The lines

2x+3y = 6 and y = -5/3 * x-1 have the point of intersection (-3,4)

Hence the correct option is C

Apr 7th, 2015

If you have any query, I will clarify.

I want your complete satisfaction and best rating for me.

Apr 7th, 2015

Thank you very much. I did get that answer by plugging in the coordinates and solving all 4 equations until everything was equal. Thank you for verifying. I will take your explanation to explain to my child how to do it. Thank you again.

Apr 7th, 2015

welcome.

Apr 7th, 2015

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Apr 7th, 2015
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Apr 7th, 2015
Sep 23rd, 2017
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