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solve the equation by completing the square: x^2-17x+42=0. What would the equation be after completing the sqauare

1 Answer

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Answer:

(x - 14)(x - 3)

Explanation:

x² - 17x + 42 = 0. We need to find 2 numbers that multiply to 42 and add to -17. Since the product is positive but the sum is negative, we will be focusing on negative numbers only.

-1 x -42 = 42

-2 x -21 = 42

-3 x -14 = 42

-3 and -14 add up to -17. So, this will be your answer.

(x - 14)(x - 3). If you are not sure that this is correct, you can multiply (x - 14) by (x - 3) Using the FOIL method.

(x - 14)(x - 3) = (x * x) + (x * -3) + (x * -14) + (-14 x -3) = x² + -3x + -14x + 42

-3x - 14x = -17x

The result is x² - 17x + 42

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