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Simplify : 7(c-2)²-(3c+1)(c-4)​

User Jan Wytze
by
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1 Answer

4 votes

Answer:

4c² - 17c + 32

Explanation:

To expand (c -2)², use the identity (a - b)² = a² - 2ab + b²

(c - 2)² = c² - 2*c*2 + 2²

= c² - 4c + 4

Use FOIL method to find (3c + 1)(c -4)

(3c + 1)(c - 4) = 3c*c - 3c *4 + 1*c - 1*4

= 3c² - 12c + 1c - 4

= 3c² - 11c - 4 {Combine like terms}

7(c - 2)² - (3c + 1)(c -4) = 7*(c²- 4c + 4) - (3c² - 11c - 4)

Multiply each term of c² - 4c + 4 by 7 and each term of 3c² - 11c - 4 by (-1)

= 7c² - 7* 4c + 7*4 - 3c² + 11c + 4

= 7c² - 28c + 28 - 3c² + 11c + 4

= 7c² - 3c² - 28c + 11c + 28 + 4

Combine like terms,

= 4c² - 17c + 32

User Andrei Lupuleasa
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