Question

Points A, B, C, and D lie on line segment AD. If AB = x, BC = x + 3, CD = twice the length of BC, and AD = 53, what is the value of x? What is the length of BC?

Answer 1

Point A the beginning of line and point D end of the line segment 
So ,x+x+3 +2(x+3)=53
2x+3+2x+6=53
4x+9 =53
4x =44
x=11
length of BC is 2(11+3)=28

Answer 2

Answer:

 x=11,   BC  = 14

Step-by-step explanation:

Points A, B, C, and D lie on line segment AD. If AB = x, BC = x + 3, CD = twice the length of BC, and AD = 53, what is the value of x? What is the length of BC?

AB=X             AB=11

BC=X + 3      BC= 11 + 3= 14

CD= 2(X + 3)  CD= 2(11 + 3)= 28

11+14+28=53

AD= 53

X + X + 3 + 2(X + 3) =53

2x+3+2x+6=53

4x+9 =53

   -9= -9

  4x =44

  4      4    

     x=11

length of BC is 11 + 3 = 14