4 years ago

X2+5x=3x+11 and solve by completing the square

1 answer:

7 0

$x^2+5x=3x+11\\
x^2+2x-11=0\\
x^2+2x+1-12=0\\
(x+1)^2=12\\
x+1=\sqrt{12} \vee x+1=-\sqrt{12}\\
x=-1+2\sqrt3 \vee x=-1-2\sqrt3$

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Answer:

The interval [2.5, 12.5]

Step-by-step explanation:

<em>Tchebysheff’s Theorem states that for any distribution of probabilities if k ≥ 1, at least </em>

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We need then to find a k greater or equal than 1 such that

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3 years ago

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The probability is 60% that you will get the same colour twice because one colour has more marbles that the other coloured marble.

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A freight train and an express train leave towns 390 miles apart at the same time, traveling toward one another. The freight tra

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3 years ago

Read 2 more answers

Help me asap i really need this

asambeis [7]

Answer:

Step-by-step explanation:

6/2

I hope this is right :)

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Fred's sporting goods is providing a $5 discount on a bicycle that costs $80. What is the percentage of the discount?

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Answer:

6.25%

Step-by-step explanation:

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Cross multiply

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3 years ago