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3 years ago

Solve the system by substitution. -8x – 7y = -5 -x = y

Mathematics

2 answers:

Lapatulllka [165]3 years ago

6 0

Substitute y = -x into the first equation:

-8x - 7(-x) = -5

-8x + 7x = -5

-x = -5

x = 5

Substitute x = 5 into y = -x

y = -(5)

y = -5

Answer: x = 5, y = -5

Inessa [10]3 years ago

5 0

Step-by-step explanation:

-8x -7y + 5 = 0

y = -x

substituting this value, we get:

-8x -7(-x) +5= 0

-8x +7x + 5 =0

-x +5=0

5 = x

substituting this value in the equation, we get:

-8(5) -7y + 5 = 0

-40 -7y +5=0

-35 -7y =0

7y = -35

y = -35/7

y = -5

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Answer:

Nearly 83 students did not had activity card.

Nearly 42 students had an activity card.

Step-by-step explanation:

Total number of tickets sold at homecoming = 125

Cost of each ticket without activity card = $20.5

Cost of each ticket with activity card = $15.75

Total amount earned = $2365

Let, the number of tickets sold without activity car d = k

So, the number of tickets sold without card = (Total sold - k)

= 125 - k

Now, according to the question:

$20.5(k) + $15.75(125 - k) = $2365

or, 20.5 k + 1968.5 - 15.75 k = 2365

⇒ 4.75 k = 2365 - 1968.5 = 396.5

⇒ $k = \frac{396.5}{4.75 } = 83.47$

Hence, nearly 83 students did not had activity card.

So,the number of students that had activity card = 125 - 83.47 = 41.53 ~ 42

Hence, nearly 42 students had an activity card.

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3 years ago

Kiera and Trina joined a gym. The gym offers two different payment plans. Kiera chose Plan 1 and pays $25 a month and no fee to

Lady_Fox [76]

Answer:

t1 = $25m

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Step-by-step explanation:

Here we want to write equations

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3 years ago

The sum of -7.68 and it’s additive inverse is??

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3 years ago

A total of 50 juniors and seniors were given a mathematics test. The 35 juniors attained an average score of 80 while the 15 sen

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Answer:

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Firstly, we need to calculate the total score of the junior students and the total score of the senior students.

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3 years ago

Mario is constructing a wall around a rectangular area which will cover a maximum of 60 square feet. The length of the wall will

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Answer:

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Step-by-step explanation:

Given

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Required

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3 years ago