For this case we have the following statement:
"You have 2 meters of fabric and you cut 85% to make curtains, 50% of the rest to make the strips that hold it. How many centimeters of fabric were left?"
So, we have:
2 meters ---------> 100%
x ----------------------> 85%
Where "x" represents the amount of fabric meters equivalent to 85%.

Thus, 1.7 meters of fabric were used to make curtains.
There are 0.3 meters of fabric left, of which half (50%) is used to make the strips that hold the curtain. That is to say:

Thus, 0.15 meters of fabric remain.

Thus, 15 cm of fabric remain
Answer;
15 cm