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3 years ago

7x - 3y = 31 7x + y = -1 Please solve x and y

Mathematics

1 answer:

Vika [28.1K]3 years ago

4 0

Answer:

(1, -8)

y= -8

x= 1

Step-by-step explanation:

7x-3y= 31

7x+y= -1

solve the equation

7x-3y=31

7x= -1-y

substitute the value of 7x into an equation

-1-y-3y=31

subtract -y to -3y

-1-4y=31

add both sides by 1

-4y=32

divide both sides by -4

y= -8

substitute the value of y into an equation

7x= -1-(-8)

distribute

7x=7

divide both sides by 7

x=1

(1, -8)

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