Question

Jon and Ed are discussing their cell phone plan for text messaging. Jon pays $20 a month for his phone and $0.15 per text message he sends. Ed’s cell phone costs $30 a month and $0.10 for each text message. Using the information above determine how many text messages they can send for their bill to be the same

Answer 1

Answer: 200 texts

explanation:
use y = mx + b
y = cost of phone bill
m = price per text
x = # of texts
b = price of phone for the month

jon’s bill: y = .15x + 20
ed’s bill: y = .10x + 30

set them equal to each other bc you want to find how many texts for their bill to be equal

.15x + 20 = .10x + 30 (subtract .10x and 20 from both sides)
.05x = 10
x = 200 texts