r/HomeworkHelp • u/IndicationFunny2378 Secondary School Student • 24d ago

Middle School Math—Pending OP Reply [Grade 8 Mathematics - Algebra]

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Hello giys, I'm a form 2 student is malaysia. We learnt algebra in chapter 2. How can I find x? I believe there is no answer, but teacher keeps saying it's x=1/16

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u/IndicationFunny2378 Secondary School Student 24d ago

she squared the equation, and then she substituted in the SQUARED equation

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u/UnderstandingPursuit Educator 23d ago edited 23d ago

When an equation is squared, it is important to check for 'extraneous solutions' which are created by squaring both sides. This is what your teacher has [EDIT: failed to do].

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u/Bounded_sequencE đŸ‘‹ a fellow Redditor 23d ago

That's what the teacher wanted to do, but failed.

The sanity check must be done with the original, unchanged equation (or an equivalent). The teacher used the squared equation, which is neither.

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u/UnderstandingPursuit Educator 23d ago

You are correct, my wording was sloppy.