Work Step by Step
RECALL: $(a+b)^2=a^2+2ab+b^2$ Use the formula above to have: $(t+7a)^2 \\=t^2+2(t)(7a)+(7a)^2 \\=t^2+14at+49a^2$
You can help us out by revising, improving and updating this answer.Update this answer
After 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.