#### Answer

$x=9$

#### Work Step by Step

"Sum" indicates addition.
$3+4+x=16$ $\longrightarrow$combine like terms
$7+x=16$ $\longrightarrow$addition property
$7+x-7=16-7$ $\longrightarrow$combine like terms
$x=9$

Published by
Pearson

ISBN 10:
0321955048

ISBN 13:
978-0-32195-504-3

$x=9$

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