Elimination

Hello everyone,

May someone explains why in the solution to this problem, https://brilliant.org/practice/elimination/?p=6, after doubling everything on the first scale, so we get four negative circles + two squares balancing with 2 and one positive circle + two squares balancing with 12.

Why I don t understand is why after doubling everything, which rule we apply here two combine the two scales by this way :

four negative circles + two squares+ 2 on one side and one positive circle + two squares + 12 on the other side?

Thank you

Easy Math Editor

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`2 \times 3`	$2 \times 3$
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Comments

It doesn't matter whether we add the items to the left-hand side of the scale or the right-hand side of the scale.

For example, suppose we are given $A = B$ and $C = D$ , then adding both these equations yield $A + C = B + D$

or we can also get $B + C = A+D$

In the future, if you have concerns about a problem's wording/clarity/etc., you can report the problem. See how here.

Brilliant Mathematics Staff - 3 months, 3 weeks ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$