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

85 * (1-.25)^x

Step-by-step explanation:

The original cost of the book is 85 dollars

The book depreciates by 25%, so it will cost (1-25%) each time it is sold

The new cost is the original cost times depreciation

cost = 85 * (1-.25)^x  where x is the number of owners

A. f(x) = 85(1 – 0.25)x

Step-by-step explanation:

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15