Question 332623
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 4x\ +\ 9y\ =\ 30]

*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 4(3)\ +\ 9y\ =\ 30]

Do the arithmetic.

Add *[tex \LARGE -4x] to both sides, then multiply by *[tex \LARGE \frac{1}{9}]

Then insert 3 in place of *[tex \LARGE x] and do the arithmetic again.  If you don't get the same answer both times, check your arithmetic.

John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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