Answer:167 text messages
Explanation:
Let x represent the number of text messages sent when either Horizon Phone Company or G-Mobile is used.
Let y represent the total cost of sending x messages using Horizon Phone Company.
Let z represent the total cost of sending x messages using G-Mobile.
Horizon Phone Company charges $16 a month plus 5 cents($0.05) per text. This means that
y = 16 + 0.05x
G-Mobile charges $21 per month with 2 cents(0.02) per text. This means that
z = 21 + 0.02x
To determine the number of texts that texts would be sent for the two plans cost the same, we would equate y to z. It becomes
16 + 0.05x = 21 + 0.02x
0.05x - 0.02x = 21 - 16
0.03x = 5
x = 5/0.03 = 167