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2 years ago

X + 3y + 2z = 7

Mathematics

2 answers:

omeli [17]2 years ago

7 0

Step-by-step explanation:

x + 3y + 2z = 7

2x − y + z = 9

-x + 4y + 5z = 14

First add the first and third equations to eliminate x.

7y + 7z = 21

Simplify:

y + z = 3

Solve for y:

y = 3 − z

Substitute into the first two equations:

x + 3(3 − z) + 2z = 7

2x − (3 − z) + z = 9

Simplify:

x + 9 − 3z + 2z = 7 → x − z = -2

2x − 3 + z + z = 9 → 2x + 2z = 12 → x + z = 6

Add the equations to eliminate z.

2x = 4

x = 2

Therefore, z = 4 and y = -1.

Ann [662]2 years ago

5 0

Just use photomath that’s easier

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Answer:

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Step-by-step explanation:

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2 years ago

Manuel earns $7.25 per hour helping his neighbor. Last month he earned $348. Choose the correct equation and solution which dete

zysi [14]

Answer:

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Step-by-step explanation:

Giving the following information:

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2 years ago

There are 22 rows of seats on a concert hall: 23 seats are in the 1st row, 27 seats on the 2nd row, 31 seats on the 3rd row, and

JulijaS [17]

We can model this situation with an arithmetic series.
we have to find the number of all the seats, so we need to sum up the number of seats in all of the 22 rows.

1st row: 23
2nd row: 27
3rd row: 31
Notice how we are adding 4 each time.

So we have an arithmetic series with a first term of 23 and a common difference of 4.

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Sₙ = (n/2)(t₁ + tₙ)

where n is the term numbers, t₁ is the first term, tₙ is the nth term

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tₙ = t₁ + (n-1)d,

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tₙ = 23 + (n-1)(4)

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2 years ago

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max2010maxim [7]

The horse traveled 439.6 feet after walking around the track 5 times

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$C = 2 \pi r$