# Please show me the workings of this no.2?

##### 2 Answers

This is direct scalar multiplication and then subtraction of matrices.

#### Explanation:

Scalar multiplication of matrices simply means that each element in the matrix is multiplied by the constant. So, each element in A will be multiplied by 2.

Then, matrix subtraction (and addition) is performed by element by element subtraction.

So, in this case, 2(-8) = -16. Then, you will subtract the 1 in the upper right corner of B to give -16 - 1 = -17.

So, a = 17

#### Explanation:

Given that

Then

Given that

So for the element