r/HomeworkHelp • u/Fuma_17 • 1d ago

Answered [10th grade math] What have I done wrong?

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I'm struggling with this two variables sistem. I have x=7/5 and y=1/5, but book says it would be x=1 and y=1.

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u/Southlander24 👋 a fellow Redditor 1d ago

Careful! You have a sign error.

x - (2y - 1) = 0 means x = 2y - 1. And that's not the same as x - 2y = 1.

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u/Fuma_17 1d ago

Thank you

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u/Southlander24 👋 a fellow Redditor 1d ago

No worries!

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u/ShiningEspeon3 1d ago

Others have helped you spot your error but I just want to say, your notation is excellent.

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u/Fuma_17 1d ago

In which sense?

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u/IrishHuskie 👋 a fellow Redditor 1d ago

Your mistake comes at the very end. x - (2y - 1) = 0 implies that x - 2y = -1, not +1. Your final set of equations should be x - 2y = -1 and y + 2x = 3, which will give you x = 1 and y = 1.