The number of text messages that will result in the exact same charge from both companies is 500
Solution:
Let "x" be the number of text messages
Cell phone A charges $20 per month plus $0.05 per text
Thus, a equation for cell phone A is framed as:
Cell phone A : 20 + 0.05(number of messages)
Cell phone A : 20 + 0.05x --------- eqn 1
Cell phone company B charges $10 per month plus $0.07 per text message
Thus, a equation for cell phone B is framed as:
Cell phone B: 10 + 0.07(number of messages)
Cell phone B : 10 + 0.07x ---------- eqn 2
For exact same charge from both companies, eqn 1 must be equal to eqn 2
[tex]20+0.05x = 10+0.07x\\\\0.07x - 0.05x = 20-10\\\\0.02x = 10\\\\Divide\ both\ sides\ of\ equation\ by\ 0.02\\\\x = 500[/tex]
Thus, the number of text messages that will result in the exact same charge from both companies is, 500
