Final answer:
To find the number of GB used such that both phone company bills are the same, we set up an equation to represent each company's charging scheme. After solving the equation $4 + $5x = $10 + $3x, we find that at 3 GB of data usage, the bills from both companies would be equal.
Step-by-step explanation:
To determine how many GB would be used so that a bill from each phone company is the same, we can set up an equation where the total cost from Company A is equal to the total cost from Company B:
Let's denote the number of GB as x.
Company A: $4 + $5x
Company B: $10 + $3x
To find the break-even point, we solve for x when the costs are equal:
$4 + $5x = $10 + $3x
When we solve this equation, we get:
$5x - $3x = $10 - $4
$2x = $6
x = $6 / $2
x = 3 GB
A customer would need to use 3 GB of data for the monthly bills from both companies to be equal.