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.

Plan A:

C = $80

C = cost

Plan B:

C = 0.15t + 20

C = cost; t = amount of text messages

Step-by-step explanation:

Let C = cost.

Let t = amount of text messages.

Plan A:

C = $80

Plan B:

C = 0.15t + 20

If 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 + 20

Isolate 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 = 0.15t

60 = 0.15t

Divide 0.15 from both sides.

(60)/0.15 = (0.15t)/0.15

60/0.15 = t

t = 400

Those who use Plan B must send at least 400 text message to have the same price as Plan A.

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step-by-step explanation: