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3 years ago

What is -2x^ -5x + 5 + 0 using quadratic formula

Mathematics

1 answer:

Mashutka [201]3 years ago

6 0

Answer:

x = -5 + √65/2 or

x = -5 - √65/2

Step-by-step explanation:

-2x² - 5x + 5 = 0

2x² + 5x - 5 = 0

Here,

a = 2

b = 5

c = - 5

Now,

Discriminant

D = b² - 4ac

= (5)² - 4(2)(-5)

= 25 + 40

= 65

D = 65 > 0

Then,

x = -b +-√b² - 4ac/2a

x = -5 +-√(5)² - 4(2)(-5)/2(2)

= -5 +-√25 + 40/4

= -5 +-√65/4

= -5 +-√65/2

x = -5 + √65/2 or x = -5 - √65/2

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