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2 years ago

Solve this system of equations using elimination with multiplication

Mathematics

1 answer:

romanna [79]2 years ago

5 0

Answer:

Step-by-step explanation:

3x - 4y = -11

x - 2y = -5

Compare the coefficients of the variables.

The coefficients of the x terms, 3 and 1, are multiples of each other.

The coefficients of the y terms, -4 and -2, are also multiples of each other.

That makes it easy to eliminate either variable.

I'll eliminate the y variables. Multiply the second equation by -2, then add it to the first equation:

₋-2x + 4y = 10

3x - 4y = -11

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x + 0y = -1 , so x = -1.

Substitute -1 for x in either equation and solve for y:

3(-1) - 4y = -11

y = 2

(x,y) = (-1, 2)

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3 years ago

The estimate of the population proportion should be within plus or minus 0.02, with a 90% level of confidence. The best estimate

Rudiy27

Answer:

The sample size required is 910.

Step-by-step explanation:

The confidence interval for population proportion is:

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The margin of error is:

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Given:

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Compute the sample size required as follows:

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3 years ago

An arithmetic sequence begins as follows: a1=13 a2=19 Which of the following gives the definition of its nth term?

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Answer:

the nth term of the sequence is $a_n=6n+7$

Step-by-step explanation:

Given : An arithmetic sequence begins as follows: $a_1=13, a_2=19$

To find : Which of the following gives the definition of its nth term?

Solution :

The nth term of the A.P is $a_n=a+(n-1)d$

The first term is $a=a_1=13$

The common difference is $d=a_2-a_1$

$d=19-13=6$

Substitute in the formula,

$a_n=13+(n-1)6$

$a_n=13+6n-6$

$a_n=6n+7$

Therefore, the nth term of the sequence is $a_n=6n+7$

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