Answer:
10 
Step-by-step
Reduce 
to 
and simply subtract.
The answer is 170. First you add base one and base two divide by twi the multiply that by the height. 18+22=40 40/2=20 20•8.5=170
Answer: Lower right corner
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Explanation:
The information that the temperature rises 3 degrees per hour will tell us the slope here. The slope is rise/run = 3/1 = 3. Each time we move up 3 on the y axis, we move 1 spot to the right.
As you can see in the bottom right hand corner graph, we start off at a temperature of 20 degrees. This is the point (x,y) = (0,20)
Then one hour later (x = 1), the temperature y bumps up to y = 23. Another hour passes by (x = 2) and y becomes y = 26. And so on.
