Answer
$17+x$
Work Step by Step
Commutative properties: $a+b=b+a,\qquad ab=ba$
Associative properties:$ a+(b+c)=(a+b)+c,\qquad a(bc)=(ab)c$
Distributive property: $\quad A(x+y)=Ax+Ay$
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$ 7+(x+10)=\qquad$
...commutative property: $x$ and $10$ can change places
$=7+(10+x)=$
...associative property: we can change groupings,
$=(7+10)+x$
= $17+x$
