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2 years ago

2x² + 9 = - 7x how do i find an answer using the quadratic formula

Mathematics

1 answer:

jok3333 [9.3K]2 years ago

7 0

Answer:

(-7 ± $i$ √(-23)) / 4

Step-by-step explanation:

Unless you have to show your work, you don't really have to use the quadratic formula unless it is unfactorable.

2x² + 9 = -7x (Add 7x to both sides)

2x² + 7x + 9 = 0 ( The quadratic formula is (-b ± √(b^2 - 4ac))/2a )

A = 2

B = 7

C = 9

(-7 ± √(49 - 72))/4

= (-7 ± √(-23))/4 (Which simplifies to an imaginary answer, proving that this is, indeed, unfactorable)

= (-7 ± $i$ √(-23))/4

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In geometry, the scale factor is a ratio of the resulting length to the initial length. Since the area of the square is equal to the square of its side length, then the scale factor is equal to:

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2 years ago

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miss Akunina [59]

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23. $\frac{4\sqrt{3} }{3}$

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