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?

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