Answer:
John can use no more than 2 GB of additional data
Step-by-step explanation:
Monthly fee = $40
Additional fee = $15 for each 1 GB of data (rounded up) over his 8 GB.
Let x be the number of additional data in GB over his 8 GB of data that comes with his plan.
Total monthly charge is
[tex]C(x)=40+15x[/tex]
It is given that monthly charge before taxes to be at most $70.
[tex]C(x)\leq 70[/tex]
[tex]40+15x\leq 70[/tex]
[tex]15x\leq 70-40[/tex]
[tex]15x\leq 30[/tex]
Divide both sides by 2.
[tex]x\leq 2[/tex]
Therefore, John can use no more than 2 GB of additional data.
