30 POINTS PLEASE HELP! Evaluate the piecewise-defined function at x=3. See picture below

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Step-by-step explanation:

For this problem, it is important to look at the domains next to the function. In this problem there is a function for when x < 1 and when x ≥ 1. 3 is greater than 1, so we will use the second equation.

From there, plug in 3 for x and solve.

-2x - 5

-2(3) - 5

-6 - 5

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astronomers is your final answer! : )

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you