Ared candle is 8 inches tall and burns at a rate of 7/10 inch per hour. a blue candle is 6 inches tall and burns at a rate of 1/5 inch per hour. after how many hours will both candles be the same height?

The heights are the same after 4 hours.

Step-by-step explanation:

The red candle burns at a rate of 7/10 inches per hour. In t hours, (7/10)t inches have burned. The height of the candle after t hours is 8 - (7/10)t.

The blue candle burns at a rate of 1/5 inch per hour. In t hours, (1/5)t inches have burned. The height of the candle after t hours is 6 - (1/5)t.

You need to find the time, t, when their heights are equal.

8 - (7/10)t = 6 - (1/5)t

Multiply both sides by 10 (the LCD).

80 - 7t = 60 - 2t

-5t = -20

t = 4

The heights are the same after 4 hours.

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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yeah i know the problem you need. i am taking it right now. the answer is step 3

~mickey