how do u do this! pls explain step by step i dont understand this at all. even photomath doesnt work for me. if u used a math calculator to do this then pls tell me the site!

(98 points) i need with 5 questions. answer definitions are welcomed, but not necessary.

∆red ≅ ∆ by rule will give brainiest if possible

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?