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2 years ago

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Mathematics

1 answer:

lawyer [7]2 years ago

4 0

Answer:

Y = [-6 6 6 -6]

Step-by-step explanation:

From the given matrices

If X - 2Y = Z

b - 2c = a ... 1

a -2d = c ...2

4+2a = 16.... 3

a + 2b = b .... 4

From3 ;

2a = 16-4

2a = 12

a = 6

From 4;

a + 2b - b = 0

a+b = 0

a = -b

6 = -b

b = -6

From1;

b - 2c = a

-6 - 2c = 6

-2c = 12

c = -6

also

a - 2d = c

6-2d = -6

-2d = -6-6

-2d = -12

d = 6

Hence the matrices Y = [-6 6 6 -6]

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<h2>Answer:</h2>

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<h2>Explanations:</h2>

Let the total number of biology textbook sold be "a"

Let the total number of psychology textbook sold be "b"

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If the number of psychology textbooks sold was 76 less than the number of biology textbooks sold, then;

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