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1 year ago

Write the standard form for a parabola that has the following x intercepts: (-4, 0) and (7, 0).

Mathematics

1 answer:

Alja [10]1 year ago

8 0

Answer:

y = x² - 3x - 28

Step-by-step explanation:

given a parabola with x- intercepts x = a and x = b , then

(x - a) and (x - b) are the corresponding factors and the equation is the product of its factors

y = (x - a)(x - b)

here the x- intercepts are x = - 4 and x = 7 , then the factors are

(x - (- 4)) and (x - 7) , that is (x + 4) and (x - 7) , then

y = (x + 4)(x - 7) ← expand using FOIL , then

y = x² - 3x - 28 ← in standard form

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Use the law of total probability:

$P(Y^{c})=P(Y^{c}|X)P(X)+P(Y^{c}|X^{c})P(X^{c})$

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Use the Bayes' theorem:

$P(X|Y)=\frac{P(Y|X)P(X)}{P(Y|X)P(X)+P(Y|X^{c})P(X^{c})}$

$=\frac{(0.90\times 0.04)}{(0.90\times 0.04)+(0.15\times 0.96)}$

$=0.20$

Thus, the proportion of women who get a positive test result are actually carrying a fetus with a chromosome abnormality is 0.20.

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