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What is the solution of the system of equations x - y = 8 and x + y = 4

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Tushar Chandra eNotes educator | Certified Educator

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The system of equations x - y = 8 and x + y = 4 has to be solved for x and y.

Add the two equations, x - y + x + y = 8 + 4

=> 2x = 12

=> x = 6

x - y = 6 - y = 8

=> y = -2

The solution of the given system of equations is x = 6 and y = -2

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givingiswinning | Student

x - y + x + y = 8 + 4

2x = 12

x = 6

x - y = 6 - y = 8

y = -2

atyourservice | Student

x - y = 8 and x + y = 4

x = 8 + y

plug this into nay of the problmes above as x

8 +y + y =4

combine

8 + 2y= 4

subtract 8

2y = 4 - 8

2y = -4

divide by 2

y = -2

now plug in into any of the problems to get x

x - (-2) = 8

x +2=8

x = 6