Question

If [ 1 4 -2 3 ] + 2M = 3 [ 3 2 0 -3 ], find the matrix M.​

Answer 1

Answer:

M×[

2

0

1

3

]=[4−7]

Order of [

2

0

1

3

] is 2×2

Order of [4−7] is 1×2

Two matrices can be multiplied if:

The number of columns of the 1

st

matrix must equal the number of rows of the 2

nd

matrix.

And the result will have the same number of rows as the 1

st

matrix, and the same number of columns as the 2

nd

matrix.

∴M must be 1×2 matrix.

[M]

1×2

×[

2

0

1

3

]

2×2

=[4−7]

1×2

[xy]

1×2

×[

2

0

1

3

]

2×2

=[4−7]

1×2

for x,y∈R

2x+0=4⇒x=2

x+3y=−7⇒3y=−7−x=−7−2=−9

⇒y=

3

−9

=−3

∴x=2,y=−3

∴M=[2−3]