Answer
$3\times(7-d)$
Work Step by Step
To rewrite a word phrase as an expression, translate each part of the phrase.
$\underbrace{3}\ \underbrace{times}\ \underbrace{the\ difference\ of\ 7\ and\ d}$
$\ \ 3\ \ \ \ \ \ \ \times \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ (7-d)$
