Victoria recently switched to a new electric company. If she uses between 0 and 400 kilowatt-hours (kWh) of electricity per month, the cost is a set price of $30. If she uses 400 kWh or more per month, the price is $0.097 per kWh.

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Answer:

see the explanation

Step-by-step explanation:

The question is

Identify the domain and the range, using words and inequalities

Let

x -----> the number of kilowatt-hours (kWh) of electricity per month

y ----> the price per month

we know that

Part 1) For the value of x between 0 kWh and 400 kWh

[tex]0\ kWh \leq x < 400\ kWh[/tex]

The price is equal to

[tex]y=\$30[/tex]

therefore

The domain is the interval ------> [0,400)

The domain is all real numbers greater than or equal to 0 kWh  and less than 400 kWh

The range is ($30)

The range is equal to $30

Part 2) For the value of x equal to 400 kWh or more per month

[tex]x\geq 400\ kWh[/tex]

The domain is the interval -----> [400, infinite)

The domain is all real numbers greater than or equal to 400 kWh

The price is

[tex]y=0.097x[/tex]

Find the range

For x=400 kWh

[tex]y=0.097(400)=\$38.8[/tex]

so

[tex]y\geq \$38.8[/tex]

The range is the interval -----> [38.8, infinite)