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Nimfa-mama [501]
3 years ago
10

Solving quadratic equations with complex solutions x2 + 4x + 8 = 0.

Mathematics
1 answer:
Daniel [21]3 years ago
4 0

Answer:

\large\boxed{x=-2\pm2i}

Step-by-step explanation:

x^2+4x+8=0\qquad\text{subtract 8 from both sides}\\\\x^2+4x+8-8=0-8\\\\x^2+2(x)(2)=-8\qquad\text{add}\ 2^2\ \text{to both sides}\\\\x^2+2(x)(2)+2^2=-8+2^2\qquad\text{use}\ (a+b)^2=a^2+2ab+b^2\\\\(x+2)^2=-8+4\\\\(x+2)^2=-4\iff x+2=\pm\sqrt{-4}\\\\x+2=\pm\sqrt{(4)(-1)}\qquad\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\x+2=\pm\sqrt4\cdot\sqrt{-1}\qquad\text{use}\ \sqrt{-1}=i\\\\x+2=\pm2\cdot i\qquad\text{subtract 2 from both sides}\\\\x=-2\pm2i

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professor190 [17]

Answer:

(- 5, 1 )

Step-by-step explanation:

- 6x - 14y = 16 → (1)

- 2x + 7y = 17 → (2)

Multiplying (2) by - 3 and adding to (1) will eliminate the x- term

6x - 21y = - 51 → (3)

Add (1) and (3) term by term to eliminate x

0 - 35y = - 35

- 35y = - 35 ( divide both sides by - 35 )

y = 1

Substitute y = 1 into either of the 2 equations and solve for x

Substituting into (1)

- 6x - 14(1) = 16

- 6x - 14 = 16 ( add 14 to both sides )

- 6x = 30 ( divide both sides by - 6 )

x = - 5

solution is (- 5, 1 )

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2 years ago
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6 0
3 years ago
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Crazy boy [7]
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7 0
3 years ago
Q is equidistant from the sides of ZTSR. Find mZRST. The
melisa1 [442]

9514 1404 393

Answer:

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Step-by-step explanation:

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Then the total angle measure of angle RST is ...

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6 0
3 years ago
A customer is late paying their renewal registration fee. The renewal registration fee is $142.16 and the late fee is 63% of the
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