Algebra
# Absolute Value

If $15<x<39$, what is the value of $|x-15|+|x-39|?$

If $9 \leq a < 29$, what is the value of $|a-9|+\sqrt{(a-29)^2}?$

If $-6\leq x\leq-4,$ what is the value of $\lvert2x+12\rvert+\lvert x+4\rvert+\lvert x-1\rvert?$