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Find the relation between x and y if, the points A(x, y), B(-5, 7) and C(-4, 5) are collinear.

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#### Solution

Given, the pointsA(x,y), B(-5,7) and C(-4,5) are collinear.

So, the area formed by these vertices is 0.

1/2[x(7-5)+(-5)(5-y)+(-4)(y-7)= 0

1/2[2x-25+5y-4y+28]= 0

1/2[2x+y+3]= 0

2x+y+3 = 0

y = -2x- 3

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