geometry
posted by Anonymous .
points a b and c are collinear if the distance from point a to point b is 8 more than twice the distance from point b to point c and the length of segment ac is 5 times the length of segment of bc, how long is segment ac

Make a sketch.
From "length of segment ac is 5 times the length of segment of bc" it is clear that AC is the longer part.
So call the endpoints of your line A and C and place B between them (doesn't really have to be to scale)
label BC = x
then AC = 5x
and AB = 4x
then it said , " the distance from point a to point b is 8 more than twice the distance from point b to point c " or
AB = 2(BC) + 8
4x = 2x + 8
2x = 8
x = 4
then AC = 5x = 20
check:
By my definitions,
BC = 4
AC =20
AB = 16
is 16 equal to 8 more than 2x4 ? YES! 
AB= 3x+3 AB=1+2x and BC=11 find x

AC=21,AB=18+x,BC=x+15. Find X