How do you solve and check your solutions to $7.2y+4.7=62.3$ ?

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Answer 1 · 2017-04-25T15:21:06

$y=8$

Don't like decimals so lets get rid of them. Multiply (all of) both sides by 10 giving:

$72y+47=623$

Subtract 47 from both sides

$72y=576$

Divide both sides by 72

$y=8$
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Check: Given that the right hand side is 62.3 consider just the left hand side

$color(red)(7.2(8))color(blue)(+4.7)$

$color(red)(56+1.6)color(blue)(+4.7)$

$56.0$
$color(white)(0)1.6$
$ul(color(white)(0)4.7) larr" add"$
$62.3$

$LHS=RHS" for "y=8color(red)(" Thus true")$

How do you solve and check your solutions to 7.2y+4.7=62.37.2y+4.7=62.3?