The resale value of a textbook decreases by 25% with each previous owner. A new textbook is sold for $85. Which function represents the resale value of the textbook after x owners? f(x) = 85(1 – 0.25)x
f(x) = 85(1 + 0.25)x
f(x) = 85(0.25)x
f(x) = (85 – 0.25)x

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  (a)  f(x) = 85(1 – 0.25)^x

Step-by-step explanation:

The growth rate is -25%, so the growth factor is 1-25% = 1 - 0.25.

Each increase in the number of previous owners causes the value to be multiplied by this growth factor, so the overall multiplier is (1 -0.25)^x

The value is the initial value times this multiplier:

  f(x) = 85(1 -0.25)^x . . . . matches the first choice

(1,4) is on graph of f(x)

f(1) = 4

so 1/4 f(x)

1/4 f(1)

1/4. ×4

1

so point for function 1/4. f(x) is (1,1)

it has the same slope and a different y-intercept

hope this : )