The first two vertices are (-7,3) (-6,1)
Slope = (3 - 1)/(-7 + 6) = -2
Opposite side of the first two vertices so the lines are parallel.
Parallel lines, slope is the same so slope is also -2
Passing thru (-4,5)
y = mx + b
b = y - mx
b = 5 - (-2)(-4)
b = 1 - 8
b = -7
Equation:
y = -2x - 7
Hope it helps.
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