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3 years ago

Solve the system of equations using row operations. Write your answer in the form (x, y).

Mathematics

1 answer:

Sonja [21]3 years ago

8 0

Answer:

(5, - 4 )

Step-by-step explanation:

Given the 2 equations

2x + 3y = - 2 → (1)

3x - y = 19 → (2)

Multiplying (2) by 3 and adding to (1) will eliminate the y- term

9x - 3y = 57 → (3)

Add (1) and (3) term by term to eliminate y

(2x + 9x) + (3y - 3y) = (- 2 + 57), that is

11x = 55 ( divide both sides by 5 )

x = 5

Substitute x = 5 into either of the 2 equations and solve for y

Substituting into (1)

2(5) + 3y = - 2

10 + 3y = - 2 ( subtract 10 from both sides )

3y = - 12 ( divide both sides by 3 )

y = - 4

Solution is (5, - 4 )

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Answer:

$8 \frac{1}{4}$

Step-by-step explanation:

Let us solve

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3 years ago

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REY [17]

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4x+18y=50
+
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3 years ago

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14. Suppose that 1 out of every 10,000 doctors in a certain region is infected with the SARS virus; in the same region, 20 out o

hram777 [196]

Answer:

The person in the at-risk population is much more likely to actually have the disease

Step-by-step explanation:

The probability of a randomly selected doctor having the disease is 1 in 1,000 (P(I)=0.0001).

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$P(I|+)=\frac{P(I)*0.99}{P(I)*0.99+(1-P(I))*0.01}\\P(I|+)=\frac{0.0001*0.99}{0.0001*0.99+(1-0.0001)*0.01}\\P(I|+)=9.9*10^{-3}$

The probability of a randomly selected person from the at-risk population having the disease is 20 in 100 (P(I)=0.20).

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3 years ago

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Doss [256]

Answer:

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3 years ago

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OverLord2011 [107]

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