Okay, I looked into the claim for myself, since you were unable to provide me with any specifics.
The "formal impeachment inquiry" was launched on Sept 24th, 2019. The very first Gallup poll solely covering a time period AFTER this date (spanning from Oct 1st-13th) showed Trump at a 39% job approval. The latest Gallup poll (Jan 16th-29th) showed Trump at a 49% job approval.
Guess what, Taco, 49-39=10. Looks like Trump can do basic math after all... Looks like YOU are the pathological liar, not Trump. I see that you are projecting your own issues onto others, just like a good little liberal does. The Marxist elite sure are proud of you!