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What is the equation of a line passing between the points below? (-3,1) (5,-7)

1 Answer

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Answer:

Ax + Ay + 2A = 0 for any nonzero A, for example (A=1): x + y + 2 = 0

Explanation:

The equation of a line is

Ax + By + C = 0

so we know that:

A*-3 + B*1 + C = 0

A*5 + B*-7 + C = 0

Let's subtract one from the other:

A*(-3 - 5) + B*(1 + -7) = 0

A*-8 + B*8 = 0

B*8 = A*8

B = A

Let's input B = A into the first two equations

A*-3 + A*1 + C = A*-2 + C = 0

A*5 + A*-7 + C = A*-2 + C = 0

checks out

C = 2A

So for any nonzero A the equation of

Ax + Ay + 2A = 0 produces a line passing between the points. Example would be

x + y + 2 = 0

User Skaz
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