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3 years ago

Can someone help with number 20

Mathematics

1 answer:

enyata [817]3 years ago

3 0

Answer:B: 36°

Step-by-step explanation:

We know that ∆ABC is isoceles, making (angle)<ABC and <BCA congruent because base angles of isoceles triangles are congruent.

Because we have parallel lines, we can look for alternate interior angle pairs. <BCA is congruent to <DAC because they're alternate interior angles.

If <BCA is x then so is <ABC.

Since triangles add up to 180° we can add all of the angles (3x+x+x) and set it equal to 180.

3x+x+x=180

5x=180

x=36

If we were looking for <BAC we would plug that back in and solve, but we're looking for <BCA which is equal to x, therefore m<BCA=36°

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3 years ago

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Answer:

b) 0.2961

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Step-by-step explanation:

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We treat trucks undergoing a brake inspection passin as a success.

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There are n independent trial.
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$P(X=x) = \binom{n}{x}.p^x.(1-p)^{n-x}$

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3 years ago

I really need help with this ?

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Answer:

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Step-by-step explanation:

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