how to solve the matrix equation

Dear sir , greetings

i hope my mail will find u in best of ur health. I m a civil engineer doing Msc in DM & RE ( Disaster Mitigation and Reconstruction Engineering ) with my major subjects in STRUCTURES.

Infact , i need you to help me to solve the matrix equations as we come accross in Advance structural analysis.

i.e Q = K .D

where Q = a matrix with 1 x column and 8 rows ( 1,2 ,3 , 4 , Q5 , Q6 , Q7 , Q8)

K = any matrix of 8 x 8 ( 8 rows and 8 colums , with all known values)

D = a matrix with 1 x column and 8 x rows (D1 , D2 ,D3 , D4 , 0,0,0,0 )

can we find the values of Q5 , Q6 , Q7 , Q8 AND D1 , D2 , D3 , D4 ?

PLZ HELP ME TO SOLVE IT STARTING RIGHT FROM ABINITIO AS I DONT KNOW EVEN HOW TO INSERT A MATRIX IN MATH CAD, I TRIED TO LEARN IT FROM TUTORIALS BUT I FAILED.

PLZ HELP ME. I WILL BE GRATEFULL

REGARDS

TAHIR ( -)