1) Side WZ is perpendicular to side WX
2) The product of the slopes of two perpedicular lines is - 1
3) The line where the side WZ lies is y = (2/3)x + 1
4) The slope of a line with formula y = mx + b is m, therefore the slope of y = (2/3)x + 1 is 2/3, and the slope of the line where the side WZ lies is - 1 / (2/3) = - 3/2
5) The equation of a line with slope m that passes through the point (a,b) is:
y - b = m (x - a)
Then the equation of our line is y - (4) = (- 3/2) (x - (-6)
=> y - 4 = - (3/2)x - 9
=> y = -(3/2)x - 9 + 4
=> y = (-3/2)x - 5
Answer: option C. y = (-3/2)x - 5