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3 years ago

What is the length of x? What is the length of EF? Only enter numbers in the answer boxes below:

Mathematics

1 answer:

dimaraw [331]3 years ago

7 0

Focus on triangles DFC and DFE:

They are both right triangles because DF is perpendicular to EC
DC=DE
DF is a common side

So, the two triangles are congruent. It follows that CF=FE, and in particular

$8x=3x+15 \iff 5x=15 \iff x=3$

And since x=3, the length of EF is

$EF=3x+15=3\cdot 3+15=24$

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Answer:

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Step-by-step explanation:

Given that,

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2 years ago

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solmaris [256]

Answer:

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Step-by-step explanation:

Assume that the probability of a defective computer component is 0.02. Components are randomly selected. Find the probability that the first defect is caused by the seventh component tested.

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Variance is:

$V = \frac{np}{(1-p)^2} = \frac{0.02}{(1-0.02)^2} = 0.0208$

The expected number of components tested before a defective component is found is 50, with a variance of 0.0208.

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