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alukav5142 [94]
2 years ago
11

X^2+2x+9=0 please?!​

Mathematics
2 answers:
Nadusha1986 [10]2 years ago
5 0

Answer:

D

Step-by-step explanation:

Given a quadratic equation in standard form : ax² + bx + c = 0

We can solve for x using the quadratic formula

x² + 2x + 9 = 0 ← is in standard form

with a = 1, b = 2 and c = 9

x = ( - 2 ± \sqrt{2^2-(4(1)(9)}) / 2

  = ( - 2 ± \sqrt{4-36}) / 2

  = (- 2± \sqrt{-32}) / 2)

  = (- 2 ± \sqrt{16(2)(-1)}) / 2

  = ( - 2 ± 4i\sqrt{2}) / 2

  = \frac{-2}{2} ± \frac{4i\sqrt{2} }{2}

  = - 1 ± 2i\sqrt{2} → D

Crank2 years ago
3 0

Answer:

Choice D is the answer.

Step-by-step explanation:

We have given a quadratic equation.

x²+2x+9 = 0

We have to find the solution of given equation.

From given equation, a = 1, b = 2 and c = 9.

x = (-b±√b²-4ac) / 2a is quadratic formula to find the solve quadratic equation.

Putting given values in formula, we have

x = (-2±√(2)²-4(1)(9) ) / 2(1)

x = (-2±√4-36) / 2

x = (-2±√-32) / 2

x = (-2±√16√-2 ) /2

x = (-2±4√2√-1) / 2                                 ∵ i = √-1

x = 2(-1±2√2i) / 2

x = -1±2√2i is the solution of given solution.

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Answer:

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Step-by-step explanation:

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If we know that A = 17.5\,cm^{2}, then the shortest length of the triangle is:

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Step-by-step explanation:

Data provided in the question:

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The correct answer is option (a) It will be closer to 30 than to 20

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