Final answer:
The error is assuming GHUK is a parallelogram, based on the congruence of sides GF and FH. To determine if GHUK is a parallelogram, we need to check if opposite sides and angles are congruent.
Step-by-step explanation:
In this question, the error is in assuming that GHUK is a parallelogram.
The fact that GF is congruent to FH does not necessarily make GHUK a parallelogram. In a parallelogram, opposite sides are congruent and opposite angles are congruent.
So, to determine if GHUK is a parallelogram, we need to check if the opposite sides and opposite angles are congruent.
If they are, then GHUK is a parallelogram.
For example, if we find that opposite sides GK and HU are congruent, and opposite angles GHK and UKH are congruent, then GHUK is a parallelogram.
However, if this condition is not met, then GHUK is not a parallelogram.
herefore, to correct the error in using properties of parallelogram, we need to verify if GHUK satisfies the conditions of opposite sides and opposite angles being congruent.
If it does, then GHUK is indeed a parallelogram.