Answer: y = 2.1
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Work Shown:
4y = 8.4
4y/4 = 8.4/4 .... divide both sides by 4; division property of equality
y = 2.1
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Check:
4y = 8.4
4*2.1 = 8.4 .... replace y with 2.1
8.4 = 8.4
We end up with a true equation, as we get the same number on both sides, so we've confirmed the answer.