<span>2/3 + y - 4/5 = 1/3
y = 1/3 - 2/3 + 4/5
y = -1/3 + 4/5
y =-5/15 + 12/15
y = 7/15</span>
BC = 18
AB = AC, hence
8x - 4 = 5x + 11 ( subtract 5x from both sides )
3x - 4 = 11 ( add 4 to both sides )
3x = 15 ( divide both sides by 3 )
x = 5
BC = 4x - 2 = (4 × 5 ) - 2 = 20 - 2 = 18
(4/9-9) and (4/0) are undefined as you can not divide by the value of 0.