If A = [049837], B = [738149] find the value of 3A – 9B - Mathematics

If A = `[(0, 4, 9),(8, 3, 7)]`, B = `[(7, 3, 8),(1, 4, 9)]` find the value of 3A – 9B

Sum

3A – 9B = `3[(0, 4, 9),(8, 3, 7)] - 9[(7, 3, 8),(1, 4, 9)]`

= `[(0, 12, 27),(24, 9, 21)] - [(63, 27, 72),(9, 36, 81)]`

= `[(-63, -5, -45),(15, -27, -60)]`

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Chapter 3: Algebra - Exercise 3.17 [Page 149]

Chapter 3 Algebra
Exercise 3.17 | Q 4. (ii) | Page 149

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