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3 years ago

X/3 +2y/3= -1 and x-y/3=9 solve. by elimination method

Mathematics

1 answer:

Galina-37 [17]3 years ago

8 0

Answer:

X=51/7, Y= -36/7

Step-by-step explanation:

X/3 + 2y/3 = -1 equ 1

X - y/3 = 9 equ 2

eliminate X/3.

X/3 + 2y/3 = -1..... x 1 ( co-efficient of X in equ2 )

X - y/3 = 9 ...... x 1/3 ( co-efficient of X in equ1 )

X/3 + 2y/3 = - 1 equ 3

X/3 - y/9 = 3 equ 4

0 + 7y/9 = -4

y = -36/7

( input the value of y into equ 4 )

X/3 -y/9 = 3

X/3 - (-36/7)/9 = 3

X/3 + 36/63 = 3

X/3 = 3 - 36/63

X/3 = 153/63

63X = 459

X = 459/63

X = 51/7.

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X/3 +2y/3= -1 and x-y/3=9 solve. by elimination method​

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