Let's get to the chart,
As it's clear if we agree with this vision that BTC in weekly time Frame can complete triangle(which is somehow ideal) we can imagine these to possible trends and prices in the future :
1-If we don't have parabolic movements just like 2017 last months according to the triangles rule, after completing the diversions and fluctuations in the triangle we will beat the previous high price(19,792$ according to the coin market cap) in middle of the middle of 2019( between April and October- most likely in July) and with Fibo Extension we can find out and come to this conclusion that price will reach the to 161.8% percent of the previous correction( the one that reach 19,792$ and touch the dip...)in last days of 2019( that price is approximately between 28,000$-32,000$) and then we draw a Fibo Retracement from bottom to the new high(28,000$-32,000$) it may have correction to the 61.8 percent that is exactly placed at the previous high(19,792$).
2-BUT If we have some parabolic movements just like 2017 last months according to the triangles rule, It will directly go to the specified TARGET(28,000$-32,000$) just like the previous analyze but in case that we get to the target sooner and we will break to triangle in the middle of its edge(sidebar).IN this CASE we will reach our TARGET in late 2018(October-December).And may have the same retrace in price just like as a said.
I'll try to ADD another Possibilities But the one that I Mentioned.