The cost to install a certain kind of floor tile is $20 per square foot. The total cost to install in an x-foot-by-x-foot room is f(x)=20x^2.
What is a reasonable domain?
How much for an 8-foot-by-8-foot?

x > 0; $1280

Step-by-step explanation:

Domain should be x > 0 because length is not negative

When x = 8

Cost = 20(8²) = 1280

3. (5x + 1) - (-10x + 6)

simplify the answer choice. combine like terms. remember to distribute the negative to the terms inside the second parenthesis. also remember that two negatives = one positive, and one of each sign = negative.

- (-10x + 6) = + 10x - 6

simplify. combine like terms:

5x + 1 + 10x - 6

5x + 10x + 1 - 6

15x - 5

∴ it is your answer

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