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3 years ago

Solve systems by substitution method x + y = 12 3x - y = 20

Mathematics

1 answer:

labwork [276]3 years ago

3 0

Step-by-step explanation:

x+y=12

3×+y=20

×=12-y

3 (12-y)+y=20

36-3y+y=20

36-4y=20

-4y=20-36

-4y= -16

y =16÷4

y=4

×+y=12

×+4=12

×=12-4

×=8

therefoer;y=4,x=8

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(6 + 7) + 8 = 21

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Step-by-step explanation:

1. By definition, the associative property of addition is:

$(a+b)+c=a+(b+c)$

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2. Therefore, if you have the following expression:

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Answer:

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2 years ago

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3 years ago

Read 2 more answers

Sam's total expenses last month were $1840. What was his total variable cost for last

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Answer:

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Step-by-step explanation:

It is given that

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Insurance premiums = $10

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Utilities = $300

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In the given problem, rent , insurance premiums, loans interest payment ad home security fee are fixed cost.

Groceries and drinks, clothes and utilities are variable cost.

So, total variable cost for last month is

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Therefore, total variable cost for last month is $1500.

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2 years ago