Question #264a7

1 Answer
Jan 22, 2018

Value of #color(brown)(b = -7)#

Explanation:

enter image source here

Given : Equation of line CD is

#4x - 6y + 2 = 0#

#2x - 3y = -1# Eqn (1)

Slope of line CD #m_(CD) = (2/3)#

Given : A (-1, -1), B (b, 8)#

Slope of AD #m_(AD) = (8+1) / (b + 1) = 9/(b+1)#

We know

#m_(CD) = - 1 / (m_(AB)#

#2/3 = -1 / (9/(b+1)) = -(b+1) / 9#

#-b -1 = (18)/3 = 6#

#color(brown)(b = -7)#