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3 years ago

Solve the quadratic equation by completing the square.

Mathematics

1 answer:

Step2247 [10]3 years ago

6 0

Answer:

x1, x2 = 4.74 , -2.74

Step-by-step explanation:

To find the roots of a quadratic function we have to use the bhaskara formula

ax^2 + bx + c

x^2 - 2x - 13

a = 1 b = -2 c = -13

x1 = (-b + √ b^2 - 4ac)/2a

x2 =(-b - √ b^2 - 4ac)/2a

x1 = (2 + √ (2^2 - 4 * 1 * (-13)))/2 * 1

x1 = (2 + √ (4 + 52)) / 2

x1 = (2 + √ 56 ) / 2

x1 = (2 + 7.48) / 2

x1 = 9.48 / 2

x1 = 4.74

x2 = (2 - √ (2^2 - 4 * 1 * (-13)))/2 * 1

x2 = (2 - √ (4 + 52)) / 2

x2 = (2 - √ 56 ) / 2

x2 = (2 - 7.48) / 2

x2 = -5.48 / 2

x2 = -2.74

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2 years ago

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Marat540 [252]

Answer:

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Step-by-step explanation:

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3 years ago

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Nookie1986 [14]

Answer:

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Step-by-step explanation:

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