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3 years ago

10

One cell phone plan charges $20 per month plus $0.15 per minute used. A second cell phone plan charges $35 per month plus $0.10

per minute used. Write and slice an equation to find the number of minutes you must talk to have the same cost for both calling plans.

1 answer:

erica [24]3 years ago

6 0

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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