2x+2y=61 2x+y=7

2x+2y=61

-2y -2y

__________

2x = 61 - 2y

___________

2 -> divide both sides by 2

x = 30.5 - y

put this x value into other equation:

2(30.5 -y) +y = 7

61 - 2y + y = 7

-y -y

______________

61 - 2y = 7 - y

+2y +2y

______________

61 = 7 + y

-7 -7

______________

56 = y

Now substitute 56 for y:

2x + 2(56) = 61

2x + 112 = 61

-2x -61 -61 -2x

__________________

51 = -2x

________

-2 -> divide both sides by (-2)

x = -25.5

Now put (-25.5) for x and 56 for y to check your answers:

2(-25.5) + 2(56) = 61

-51 + 112 = 61

61 = 61

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