Acandle is 17 inches tall after burning for 3 hours. after 5 hours , it is 15 inches tall. write a linear equation to model the relationship between height h of the candel and time t. predict how tall the candel will be after burning 8 hourse

Using the data given, you should create 2 points: (time,inches)

The 2 points should be: (3,17) and (5,15)

Then use the slope formula: (y2-y1)/(x2-x1)

(15-17)/(5-3)
-2/2
-1

So the slope end up equaling -1

Then use y=mx+b

m is the slope, and it doesn’t matter what points we plug in for x and y, but they have to be from the same point. For this, I’m gonna use (17,3)

3=(-1)(17)+b

Now solve for b

3=-17+b
+17 +17

20=b

Now your equation is: y=-1x+20

Now it asks how long after 8 hours, so we plug in 8 for x:

Y=(-1)(8)+20
Y=-8+20
Y=12

So the candle will be 12 inches long after 8 hours.