Find b such that the points A(2,b),B(5,5)and C(-6,0) are the vertices of right angled  with angle < BAC = 90 degree.

Answer:
Step-by-step explanation:
We know that the perpendicular lines have negative-reciprocal slopes.
In other words, their product is - 1.
Find the slopes of AB and AC:
Find the the product of slopes and solve for b: