Answer
$3h^2 + 6xh - 7h$
Work Step by Step
$f(x) = 3x^2 - 7x$
$f(x+h) = 3(x+h)^2 - 7(x+h) = 3x^2 + 3h^2 + 6xh - 7x - 7h$
$f(x+h) - f(x) = (3x^2 + 3h^2 + 6xh - 7x - 7h) - (3x^2 - 7x) = (3h^2 + 6xh - 7h)$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.