Me convert this to an equation with an explanation. linda is shopping for a new cell phone and rate plan. she wants to compare basic plans from two different companies. both plans will offer the same number of minutes per month, but have a charge per text message. company a's plan will charge $39.99 per month plus $0.10 per text message. company b's plan will charge $19.99 a month plus $0.20 per text message. linda wants to know how many text messages she will have to send in order for the plan costs to be the same. write an equation to model the situation. let t represent the number of text messages.

i have this question, but i would appreciate some guidance with it. i'm not the best at converting these to a proper equation. i would appreciate it if someone might me.