Upvote:3
Jesus Christ created the earth under the direction of Heavenly Father (source). As an analogy, I think of Heavenly Father as the architect and Jesus Christ as the builder.
This apparently contradicts the verses you quote from Isaiah, where the Lord asserts that He created the earth all alone. The Church of Jesus Christ of Latter-day Saints identifies Jehovah as Jesus Christ (source), so I would suggest that the speaker in the verses you linked was Jesus Christ. However, I reconcile the contradiction by considering Jehovah to be speaking on behalf of the Godhead as a single unit. The scriptures (both the Bible and the Book of Mormon) teach that the Father, the Son and the Holy Ghost are one (see for example, 3 Nephi 11:36). We understand this to mean that the Father, the Son and the Holy Ghost are completely unified in mission & intent. Compare to:
Imperfect mortals are taught to emulate the perfect example given by God. This is a discussion of alignment of the will & purpose, not an alignment of substance.
Therefore it makes sense to us for Jesus Christ to speak of the Godhead as One.