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3 years ago

use the elimination method to solve the system of equations. choose the correct ordered pair. 7x+3y=30 -2x+3y=3

Mathematics

1 answer:

andreev551 [17]3 years ago

3 0

Answer:

x = 3, y = 3

Step-by-step explanation:

Elimination method to find x:

(7x + 3y = 30) * -1 ===> -7x - 3y = -30

-2x + 3y = 3

add two equations to eliminate y ______________

-9x = -27 ===> x = 3

substitution to find y:

-2x + 3y = 3

-2(3) + 3y = 3

-6 + 3y = 3

3y = 9

y = 3

Elimination method to find y:

(7x + 3y = 30) * 2 ===> 14x + 6y = 60

(-2x + 3y = 3) * 7 ===> -14x + 21y = 21

add two equations to eliminate x ______________

27y = 81 ===> y = 3

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Nataly [62]

Answer:

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${\bf 4x}^{\bf 2}+{\bf 4y}^{\bf 2}-{\bf 8x+0y-60}={\bf 0}$

Step-by-step explanation:

The general form of the circle is

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Given points are (5,0) , (0,4) and (2,4)

Let the points (5,0) , (0,4) and (2,4) be (x_1,y_1) , (x_2,y_2) and (x_3,y_3) respectively

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Substituting the point (5,0) in (1)

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3 years ago

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Answer:

Step-by-step explanation:

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The test scores of 1,200 students are normally distributed with a mean of 83 and a standard deviation of 5.5. Under which interv

KATRIN_1 [288]

Using the Empirical Rule, it is found that the interval in which approximately 978 students scored was:

A. 72 < x < 88.5.

<h3>What does the Empirical Rule state?</h3>

It states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

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More can be learned about the Empirical Rule at brainly.com/question/24537145

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