Yes, your work is correct.
The diagram does illustrate x²+6x+9=72. This is also represented by
(x+3)² = 72
We can take the square root of both sides:

When we evaluate this, the answers are x = -11.5 or x = 5.5.
<em>4℉.</em>
What we know about Degrees is that there is a<em> </em><u><em>Positive</em></u> type and a <u><em>negative</em></u> type.
(i.e: 30℉ is <u><em>positive</em></u> and -30℉ is <u><em>negative</em></u>.)
If the temperature was -4℉ at 7AM, then it is negative. If it goes up by an amount that is more than 4 then that negative will go up to a positive temperature. In this case: At 9AM it was 8° <u><em>warmer</em></u>.
<u><em>Warmer</em></u><em> is a </em><u><em>keyword</em></u><u>.</u> If it is warmer by an amount, Negative temperatures <u><em>will go up to a positive</em></u> and positive temperature <u><em>will just go up</em></u>. If it gets cooler, negative temperatures <u><em>will go down further</em></u> and positive temperatures <u><em>will go down to a negative</em></u>.
So lets work out this problem with our newfound knowledge.
-4° F at 7AM
8° warmer at 9AM
-4 + 8 = 4.
<em>The temperature was 4° at 9AM.</em>
-Snooky
So just divide 100 by 25 which equals 4 then divide 120 by 30 which also equals to 4 and if the rest equal 4 then its proportional (1)
And then same for 2 and 3 just divided the bottom by the top and if they all get the same answer they are proportion and if one is not the same then it’s not
For the grids if the dots are line diagonally straight and it starts at the 0 then it’s proportional if not then it’s not
Hope this helps :)