Given matrices are
.
The above two matrices same dimensions,
and they can be together.
First apply scalar multiplication is done by multiplying each element of the first matrix by the scalar negative 1.
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The product of two different signs is negative and the product of two same signs is positive.
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Next add matrices by adding the corresponding elements of the matrices.
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The product of two different signs is negative and the product of two same signs is positive.
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The value of
is
.