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3 years ago

How to do 2x-8=7y and 6x-9y=-4

Mathematics

2 answers:

Galina-37 [17]3 years ago

7 0

Hello from MrBillDoesMath!

Answer:

x = -25/6

y = -7/3

Discussion:

2x - 8 = 7y => multiply both sides by 3

6x - 24 = 21y

Subtract this from the second equation:

6x -9y= -4

6x -24 = 21y

- --------------------------

0x -9y + 24 = -4 - 21y => add 21y to both sides

-9y + 21y + 24 = -4 => add -24 to both sides

-9y +21y + (24 - 24) = -4 -24 =>

12y = - 28 =>

y = -28/12

y = -7/3

Solving for x,

2x - 8 = 7(-7/3) =>

2x - 8 = -49/3 => add 8 = 24/3 to both sides

2x = -49/3 + 24/3 =>

2x = -25/3 => divide both sides by 2

x = -25/6

Thank you,

MrB

disa [49]3 years ago

6 0

Answer:

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Step-by-step explanation:

fsfddddddddds

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