Question

A Candle has been burning for 20 minutes and is now 25 cm tall. In an hour it will be 10 cm tall. Which equation models the height ,y, of the candle in centimeters ,X meters after it was a Lit. A: y-25=-4(x-20) B: y-25=-3/8(x-20) C: y+25=-.25(x+20) D: y-25=-.25(x-20)

Answer 1

Answer:

D is the correct option.

Step-by-step explanation:

The height went from 25 to 10 cm ( = 15 cm) in 60 minutes . In 20 minutes it will be reduced by 5 cm so the original height was 30 cm ( at time 0).

Looks like option D :

y-25=-.25(x-20)

At x = 0 minutes, y = 30 so:

30 - 25 = 5

-.25(0 - 20) = 5  so that fits.

At time = 20 minutes

25 - 25 = 0

-.25(20 - 20) = 0  That fits

At time 80 minutes:

10 - 25 = -15

-.25(80 - 20) = -.25 * 60 = -15   That fits.