PSEG Long Island charges its residential customers a little monthly service charge plus an energy charge based on the amount of electric used. The monthly cost of electricity is approximated by the function:
C = f(h) = 37.60+ 0.10h,
where h represents the number of kilowatt hours (kWh) of electricity used in excess of 250 kWh.

(b) Find f (90) and interpret its meaning.
f(90) =

r(0,90)(x,y) . t(-5,0)

last option

step-by-step explanation:

∆def to ∆d"e"f"

- rotate 90 counterclockwise degrees

- then translated 5 to the left (x --> x - 5)

answer is the last option

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

source

b

step-by-step explanation: