Use the given row transformation to change each matrix as indicat...

Question

Use the given row transformation to change each matrix as indicated. See Sample 1. < 2x2 Matrix > ; -4 times row 1 added to row 2

Accepted Answer

Hello, everyone. We are asked to apply the indicated row transformation to the following matrix. The matrix we are given is a two by two matrix where the first row is 38 and the second row is 85. We are asked to add the result negative five times of row one to row two. We have four answer choices all of which are two by two matrices with slightly different signs on the values of the elements. Thinking about what add the result negative five times row one to row two means this means we're going to do negative five multiplied by the element from row one and then added to the element from row two. So row one will not change starting a new matrix that stays three and eight. Nothing's changing there in row two. I'm gonna do negative five and I'm gonna multiply it by the corresponding value from row one. So the first element from row one, which is three and add that to the first element from row two, which is eight. I'm gonna do the same thing with the second element in row two. I'm gonna do negative five multiplied by the second element from row one, which is eight plus the second element from row two, which is five. And now to do the multiplication. In addition, again, our first row is still three and eight that did not change our second row negative five multiplied by three is negative plus eight is negative seven. For the second element negative five multiplied by eight is negative 40 plus a positive five is negative 35. So our answer is a two by two matrix where the first row is 38 and the second row is negative seven, negative 35. And this matches answer choice D have a nice day.

Struggling with College Algebra?

Use the given row transformation to change each matrix as indicated. See Sample 1. < 2x2 Matrix > ; -4 times row 1 added to row 2

Watch next

Introduction to Matrices practice set