Answer:
300 minutes
Step-by-step explanation:
Let
x----> the numbers of minutes used
y ---> the cost per month
we know that
<em>First cell phone plan</em>
y=0.15x+20 ---> equation A
<em>Second cell phone plan</em>
y=0.10x+35 ---> equation B
equate the equation A and equation B
0.15x+20=0.10x+35
Solve for x
0.15x-0.10x=35-20
0.05x=15
x=15/0.05
x= 300 minutes
Find the cost y
y=0.15(300)+20 =$65
That means
For x=300 minutes
The cost for both calling plans is y=$65
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If you translate it to English I’ll answer for you
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