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2 years ago

Solve the question by completing the sqaure x² + 4x = 0?

Mathematics

1 answer:

n200080 [17]2 years ago

3 0

Answer:

x = 0 or -4

Step-by-step explanation:

x² + 4x = 0

To complete the square, take half of the middle coefficient, square it, then add to both sides.

(4/2)² = 2² = 4

x² + 4x + 4 = 4

(x + 2)² = 4

x + 2 = ±2

x = -2 ± 2

x = 0 or -4

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Read 2 more answers

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Check below

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1. Definition for intervals

$(a,b)=\left \{ x\in\Re : a$

2. Functions

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Let's perform graph tests.

That's an one to one, injective function. Look how any horizontal line touches that only once. Also, It's a surjective and a bijective one.

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Surjective.

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General function

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2 years ago