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1 year ago

2x^2+8x-3=-1 Solve by completing the square.

Mathematics

1 answer:

algol131 year ago

8 0

Answer:

step 1. Halve everything

x^2+ 4x - 0.5 = 0

step 2. Halve the coefficient of x so you can write down an equivalent for x² + 4 (that is, (x + 2)^2 - 4 )

(x + 2)² - 4.5 = 0

step 3. Isolate the squared term:

(x + 2)^2 = 4.5

step 4. Take square roots of both sides, recognising that a square root can be positive or negative:

x + 2 = ±√4.5

step 5. Make x explicitly

x = -2 ±√4.5

And there you are with two solutions.

Step-by-step explanation:

hope this helps if not let me know have a great day

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Answer:

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Step-by-step explanation:

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2 years ago

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Answer:

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Step-by-step explanation:

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Let's start with what we know:

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