<prompt> Ikiwa mathbfv nyakati mathbfw anzapmatrix 2 7 -13 endpmatrix, basi tafuta mathbfw mara mathbfv .  <response>: Tuna hiyomathbfw nyakati mathbfv -mathbfv nyakati mathbfw anzapmatrix - 2 -7 13 mwishopmatrix. 