Q:

Daniel is choosing between two cellphone plans. "Plan A" charges $80 per month, which includes unlimited text messaging. "Plan B" costs $20 per month plus $0.15 per text message. What is the system of equation that represents the fees of both "Plan A" and "Plan B"? Identify what your variables represent.

Accepted Solution

A:
Answer:Plan A:C = $80C = costPlan B: C = 0.15t + 20C = cost; t = amount of text messagesStep-by-step explanation:Let C = cost. Let t = amount of text messages. Plan A:C = $80Plan B:C = 0.15t + 20If the next question asks for you to solve when Plan B will be equal to Plan A, set the two equations equal to each other. 80 = 0.15t + 20Isolate the variable, t. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS. First, subtract 20 from both sides. 80 (-20) = 0.15t + 20 (-20)80 - 20 = 0.15t60 = 0.15t Divide 0.15 from both sides. (60)/0.15 = (0.15t)/0.1560/0.15 = tt = 400Those who use Plan B must send at least 400 text message to have the same price as Plan A. ~