MATHEMATICS HIGH SCHOOL

You are given the system of equations to solve by the elimination method, which is an INCORRECT step that will NOT produce a system with the same solution?2x + y = −10
3x + 4y = −20

A) multiply the first equation by 4 and subtract the second equation
B) multiply the first equation by −4 and add the second equation
C) add 8 times the first equation and −2 times the second equation
D) multiply y by 4 in the first equation and subtract the second equation

Answers

Answer 1
Answer:

Answer:

Option D) multiply y by 4 in the first equation and subtract the second equation

Step-by-step explanation:

we have

2x+y=-10 ----> first equation

3x+4y=-20 ---> second equation

Verify each case

case A) multiply the first equation by 4 and subtract the second equation

so

(2x+y)*4=-10*4 ------> 8x+4y=-40

[8x+4y=-40]-[3x+4y=-20] -----> 5x=-20 -----> x=-4

This step is correct

case B) multiply the first equation by -4 and add the second equation

so

(2x+y)*-4=-10*-4 ------> -8x-4y=40

[-8x-4y=40]+[3x+4y=-20] ----->-5x=20 -----> x=-4

This step is correct

case C)  add 8 times the first equation and −2 times the second equation

so

(2x+y)*8=-10*8 ------> 16x+8y=-80

(3x+4y)*-2=-20*-2 ----> -6x-8y=40

[16x+8y=-80]+[-6x-8y=40] ----->10x=-40 -----> x=-4

This step is correct

case D) multiply y by 4 in the first equation and subtract the second equation

so

2x+4y=-10

[2x+4y=-10]-[3x+4y=-20] -----> -x=-10+20 -----> x=-10

This step is incorrect

NOT produce a system with the same solution

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Answers

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Answers

Answer:

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Step-by-step explanation:

To find the average/mean of a set of values, you add all the values together, then divide them by the amount of values in the set.

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Hope this helps!

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A=
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C=
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Answers

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Step-by-step explanation:

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Answers

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!!URGENT!!Camila has had a collection of sports cards for several years. If the time in years since the collection started is represented by t, and the number of cards in the collection is represented by B, match each of the statements below with an equation that models the function described. Camila had started her collection with 250 cards and her collection decreased by 60 cards each year. Camila didn't have any cards when she started her collection, but her collection grew by 60 cards each year.

Answers

Answer:

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Step-by-step explanation:

"Camila started her collection with 250 cards and decreased by 60 cards each year"

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Answers

Answer:

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Step-by-step explanation:

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