A matrix completion problem asks whether a partial matrix composed of specified
and unspecified entries can be completed to satisfy a given property. This work
focuses on determining which patterns of specified and unspecified entries correspond
to partial matrices that can be completed to solve three different matrix equations.
We approach this problem with two techniques: converting the matrix equations into
linear equations and examining bases for the solution spaces of the matrix equations.
We determine whether a particular pattern can be written as a linear combination of
the basis elements. This work classifies patterns as admissible or inadmissible
based on the ability of their corresponding partial matrices to be completed
to satisfy the matrix equation. Our results present a partial or complete
characterization of the admissibility of patterns for three homogeneous linear matrix
equations.