"It is on the bottom left."
In Japanese, diagonals are described as migi-ue, migi-shita, hidari-ue, and hidari-shita. Both Japanese and English have rules for which half to say first, to avoid mishearing or miscommunicating. It’s just that when the rule was made, English opted for vertical first, while Japanese decided on horizontal first.
I am confused by the choice of verb here - and the confusion is caused by another question in this lesson which asks us to translate "The chair is under that." In this question we appear to be talking about an agreed upon subject, "it". We have pointed at it, or asked about it already prior. And we are answering: "It is on the bottom left." Shouldn't this use です? The use of あります would imply to me that we are saying "There is a thing on the bottom left."
I had thought, perhaps, that "です" was simply not appropriate for specifying the place an object is in. But the "other question" I reference uses it in its answer. In that case, the "chair" is also understood to be an already introduced subject and です is used for indicating exactly where it can be found.
So - I suppose - this is a long way of asking why です is inappropriate as the verb in this answer.