Marika is training for a track race. she starts by sprinting 100 yards. she gradually increases her distance, adding 4 yards a day for 21 days. which explicit formula models this situation? a. an = 100 + (n – 1)21 b. an = 21 + (n – 1)4 c. an = 100 + (n – 1)4 d. an = 4 + (n – 1)100

I think it's C

Step-by-step explanation:

I'm not 100% sure but thats what i would guess.

C.

Step-by-step explanation:

Given,

Initial distance Marika covered = 100 yards,

Also, She gradually increases her distance by 4 yards,

Thus, the difference between the distance of consecutive days is 4 yards,

So, there is an AP that shows the given situation,

Having first term, a = 100,

Common difference, d = 4,

Since, the explicit formula of an AP is,

Which is the required formula.

Option 'C' is correct.

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.'

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