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3 years ago

I need the answer fore both plsss

Mathematics

1 answer:

grandymaker [24]3 years ago

5 0

Answer: 6i) 6a² - 2ab

6ii) -2b³

6iii) b³ + 7b² - 49b

Step-by-step explanation:

6i) (a + b)(5a - 3b) + (a - 3b)(a - b)

= 5a² - 3ab + 5ab - 3b² + a² - ab - 3ab + 3b²

= 5a² + 2ab - 3b² + a² - 4ab + 3b²

= 6a² - 2ab

6ii) (a - b)(a² + b² + ab) - (a + b)(a² + b² - ab)

= a³ + ab² + a²b - ab² - a²b - b³ - (a³ + ab² - a²b -ab² + a²b + b³)

= a³ - b³ - (a³ + b³)

= a³ - b³ - a³ - b³

= -2b³

6iii) (b² - 49)(b + 7) + 343

= b³ + 7b² - 49b - 343 + 343

= b³ + 7b² - 49b

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Please post #7 on a different question.

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Given:

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3 years ago

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Scorpion4ik [409]

Answer:

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Step-by-step explanation:

When you have an equation, your goal is to get the letter you are solving for alone. To do this, you employ a simple rule: what you do to one side of the equals sign, you must do the other.

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