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2 years ago

Solve by elimination 7x+7y=-7 -10x-7y=28

Mathematics

2 answers:

Sergeeva-Olga [200]2 years ago

8 0

Answer:

x = -7

y = 6

Step-by-step explanation:

7x + 7y = -7 ------------------(I)

-10x - 7y = 28 ----------------(II)

Add both the equation and so y will be eliminated and we can find the value of x

(I) 7x + 7y = -7

(II) <u>-10x - 7y = 28 </u> {Now add}

-3x = 21 {Divide both sides by (-3)}

x = 21/-3

x = -7

Plugin x = -7 in equation (I)

7*(-7) + 7y = -7

-49 + 7y = -7

7y = -7 + 49

7y = 42

y = 42/7

y = 6

Zarrin [17]2 years ago

7 0

Answer:

x = - 7, y = 6

Step-by-step explanation:

7x + 7y = - 7 -----> equation 1

- 10x - 7y = 28 -----> equation 2

Add equations 1 & 2,

7x + 7y = - 7

- 10x - 7y = 28

___________

- 3x + 0 = 21

- 3x = 21

x = 21 / - 3

x = - 7

Substitute x = - 7 in equation 1,

7x + 7y = - 7

7y + 7x = - 7

7y + 7 ( - 7 ) = - 7

7y - 49 = - 7

7y = - 7 + 49

7y = 42

y = 42 / 7

y = 6

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3 years ago

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Answer:

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Please check the attachment for the table, it will aid you in understanding the solution

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10,792,400 in word form

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