Ex 9.3, 5 (c) - Chapter 9 Class 8 Algebraic Expressions and Identities

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Ex 9.3, 5 (c) Subtract: 3l (l – 4 m + 5 n) from 4l (10 n – 3 m + 2 l) Simplifying expressions 3l (l – 4m + 5n) = (3l × l) + (3l × –4m) + (3l × 5n) = 3l2 – 12lm + 15ln 4l (10 n – 3 m + 2 l) = (4l × 10n) + (4l × –3m) + (4l × 2l) = 40ln – 12lm + 8l2 = 8l2 – 12lm + 40ln 4l (10 n – 3 m + 2 l) = (4l × 10n) + (4l × –3m) + (4l × 2l) = 40ln – 12lm + 8l2 = 8l2 – 12lm + 40ln Putting like terms below like terms. So, our answer is 5l2 + 25 ln