If 
find matrix C such that 5A + 3B + 2C is a null matrix.
5A + 3B + 2C = 0
= 
+3
+2
=
= 
+
+
=
=
= 
…… (i)
= 
…… (ii)
= 
…… (iii)
= 
…… (iv)
= from equations (i),(ii),(iii),(iv), we get
= 
= 
= 
= 
= 
=
Hence, C = 
12
If find matrix C such that 5A + 3B + 2C is a null matrix.
5A + 3B + 2C = 0
= +3+2=
= ++=
=
= …… (i)
= …… (ii)
= …… (iii)
= …… (iv)
= from equations (i),(ii),(iii),(iv), we get
=
=
=
=
=
=
Hence, C =