We will assume that we need to find the equation for the length of the candle.

A candle that has been burning for 2 minutes is 8 inches long. That same candle is 7 1/4 inches long after burning 3 minutes. Assume that the candle will continue to burn at this same rate.

Let 'x' denotes the time since the candle was lit. We will use x to write a function y = y(x) for the length of the candle.

The above bold information represents the coordinate points for the linear equation: (3,7.25) and (2, 8)

Now we can find the slope m:

m=(y2-y1)/(x2-x1),

m=(8-7.25)/(2-3)

m = -0.75

Next, we use one coordinate point and the slope to write the point-slope equation:

y-y1=m(x-x1)

y-8=-0.75(x-2)

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click here to see the equation solved for y

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y = -0.75x + 9.5

The equation that describes the length of the candle is y = -0.75x + 9.5.