Parallel lines have the same slope, so in y = mx +b, m would have the same value for both.
In perpendicular lines, the value of the m is inversed. Because the m is over an invisible one in this case, m/1(x) becomes -1/m(x), making the equation y = 1/m(x) + b
Point-slope form is (y - y1) = m (x - x1), meaning that the first term of y subtracted from the zeroth term of y is equivalent to m multiplied by the value of the first term of x from the zeroth term of x
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