{"id":"act_quizme:math:q1:06","source_id":"act_quizme","source_item_id":"math-q1-06","external_id":"8387a20d062c608a","program":"ACT","section":"math","category_code":null,"category":null,"subcategory_code":null,"subcategory":null,"form_id":null,"passage_id":null,"position":6,"scored":true,"layout_warning":null,"stem":"Which of the following matrices is equal to 5 the 2 by 2 matrix with first row negative 4, 2 and second row 0, negative 5 5 [ - 4 2 0 - 5 ] ?","stimulus":"","stimulus_html":null,"stem_html":"

Which of the following matrices is equal to 5 the 2 by 2 matrix with first row negative 4, 2 and second row 0, negative 5 5 [ - 4 2 0 - 5 ] ?

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F. Incorrect. You may have started by correctly multiplying all the matrix elementsby 5: [5-450][525-5]=[-200][10-25] . Then, you may have incorrectly added the elements in the same column: [-20+010+-25]=[-20-15] .

G. Incorrect. You may have started by correctly multiplying all the matrix elementsby 5: [5(-4)5(2)5(0)5(-5)]=[-20100-25]. Then, you may have incorrectly added the elements in the same row: [-20+100+-25]=[-10-25].

H. Incorrect. You may have added 5 to each of the matrix elements rather than multiplying: 5[-420-5]→[5+-45+25+05+-5]=[1750].

J. Correct. When multiplying a matrix by a number, distribute that number to each ofthematrix elements. Here, each element in the matrix will be multiplied by 5: 5[-420-5]=[5(-4)5(2)505(-5)]=[-20100-25].

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the 1 by 2 matrix with first row negative 20, negative 15 [ - 20 - 15 ]

","ord":0},{"label":"G","content_html":"

the 2 by 1 matrix with first row negative 10 and second row negative 25 [ - 10 - 25 ]

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the 2 by 2 matrix with first row 1, 7 and second row 5, 0 [ 1 7 5 0 ]

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the 2 by 2 matrix with first row negative 20, 10 and second row 0, negative 25 [ - 20 10 0 - 25 ]

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