In Exercises 9 - 16, find the following matrices: b. A - B
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Question

In Exercises 9 - 16, find the following matrices: b. A - B

Matrices A and B for exercise 11 in college algebra, chapter on matrices and determinants.

Accepted Answer

Hey everyone, welcome back in this problem. We are asked to perform the following matrix operation A minus B. We have A and B are three by two matrices. A has the first column 764. The second column 158. And B has first column 418. And second column negative seven negative 90. Okay. When we're subtracting matrices, we want to do is double check that they're the same dimension. Okay. In this case they are they're both through by two matrices. So we're okay to do the subtraction. So let's write out A minus B what we're looking for And let's write this out in terms of our matrices. So a 764 in the first column 1,58 in the second column minus B. 418. In the first column negative seven negative 90. In the second column. Now when we're subtracting matrices, what we're gonna do is we're going to subtract element wise. Okay, so we're gonna take the element in A and subtract the corresponding element and be So let's start with the first element. Okay, so the first row, first column in A. We have seven And in B we have four. Okay. And so we are going to get 7 -4 as the first element in the resulting matrix. Hm Alright. Doing the same thing for the next element. Okay. We have row two column one, A has six. B. Has one. Okay, so in our resulting matrix in that same position, we're gonna have six minus one. All right, we're going to continue to do the same thing for the other elements. So in the bottom left we're gonna have 4 - in the top rate we have one minus negative seven in the second row. Second column we have five minus negative nine. And in the bottom right? 8 0. Okay. So we're just subtracting the corresponding elements And working this out. This is going to give us three 5 -4 in the first column. Eight 14 eight in the second column. Okay. And that's our answer. That's the result of a minus B. Okay. And that's going to correspond with answer B. Yes. We're resulting Matrix A minus B is 35 negative four. In the first column 8 14 8 in the second column. That's it for this video. I hope that helped see you in the next one.

In Exercises 9 - 16, find the following matrices: b. A - B

Key Concepts

Matrix Subtraction

Matrix Dimensions

Representation of Matrices

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