Question

Marjorie got a total 239 points on three tests. The combined scores on the scores on the second two tests were 59 more than the score on the third test. The score on the second test was 25 points more than the score on the third test. Write a matrix a matrix equation for this situation.

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Answer 1

Option a is the correct answer.

Explanation:

Let x,y and z represent the marks scored in first,second and third tests respectively.

Total score is 239, then:

x+y+z = 239 -------1

Combined scores of first and second tests is 59 more than that of third test,then:

x+y = 59+z

x+y-z = 59 ---------2

The score of second test is 25 more than that of third test, then:

y = 25+z

0x+y-z = 25 --------3

The matrix equation for this situation is:

`\left[\begin{array}{ccc}1&1&1\\1&1&-1\\0&1&-1\end{array}\right]`
`\left[\begin{array}{c}x&y&z\end{array}\right]=`
`\left[\begin{array}{c}239&59&25\end{array}\right]`.