In Exercises 9 - 16, find the following matrices: c. - 4A

Question

Matrix A and B displayed with their elements for college algebra exercises.

Accepted Answer

Hey everyone in this problem we are asked to perform the following matrix operation. The operation is negative three A. Okay. And the a matrix were given is 764 in the first column and 158 in the second column. Okay so a three by two matrix. Okay so we're asked to do -3 a. Okay so let's write this in terms of our matrix we have negative three times our matrix. A 764 in the first column. 158 in the second column. Now when we're multiplying a matrix by a constant we can bring that constant inside of the matrix and we're going to multiply it to every single element of that matrix. Okay so this is going to become the matrix where we have negative three times seven -3 times six -3 times four negative three times one negative five. Oops sorry negative three times five negative three times five and negative three times eight. Okay so we brought that three in negative three in and we're multiplying it by every single element in our matrix. Okay so now multiplying out, we're gonna get negative 21 negative negative 12 - -15. And -24. And that's it. That's our -3. A. And that is going to correspond if we move down a little bit here with answer D. Okay so the resulting negative three A. Is gonna be negative 21 negative 18 negative 12 in the first column negative three negative 15 negative 24 in the second column. That's it for this one. Thanks everyone for watching See you in the next video.

In Exercises 9 - 16, find the following matrices: c. - 4A

Key Concepts

Matrix Scalar Multiplication

Matrix Notation and Elements

Properties of Matrices in Algebra

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