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Solve 2x2 + 5x = 12

Here are the answers provided
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x = three over two and x = −4
x = 2 and x = −3
x = −6 and x = 5
x = one half and x = one over three

User Trungvose
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2 Answers

10 votes
The answer to this question is A
User Cornholio
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9 votes

Answer:

A

Explanation:

2x² + 5x = 12

2x² + 5x - 12 = 0

x² + 5x - 24 = 0

factors of 24 are 1, 2, 3, 4, 6, 8, 12, 24. the only pair that adds to 5 is 8 and 3

2x² - 3x + 8x - 12 = 0

split the equation and factor

2x² - 3x = 0 ||| 8x - 12 = 0

x(2x - 3) ||| 4(2x - 3)

therefore the pair is (2x - 3)(x + 4)

2x - 3 = 0

2x = 3

x = 3/2

or

x + 4 = 0

x = -4

User Ceran
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