Answer: 200 messages
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Check out https://brainly.com/question/11754609 for a similar problem
Plan A's cost equation is y = 0.10x + 30
Plan B's cost equation is y = 50
Equate the two right hand sides, then solve for x
0.10x + 30 = 50
0.10x = 50-30
0.10x = 20
x = 20/0.10
x = 200
If you send/receive 200 messages, then the two plans will both cost the same ($50) per month.
