Farenhite conversion of -11℃:
1.8(-11)+32
-19.8+32
12.2℉
difference between 12.2℉ and -80℉:
12.2+80
92.2℉ difference
Answer:
78
Step-by-step explanation:
You take the original total: 60, and multiply it by 30 to get 1,800. You then divide 1,800 by 100 to get 18. 18 is your 30%. Now, you add the 30% to 60 getting your total number of ducks: 78.
The equation version:

It is just proportions.
Answer:
(2x - 1)^2
Step-by-step explanation:
We can reverse engineer the solution...
to complete the square, we know (2x + __)^2 will generate the 1st term 4x^2
To generate the 2nd term, we will need -1, so (2x - 1)^2....
When expanded, we will have 4x^2 - 4x + 1, which we completed the square.
Let S, M, L represent the shortest, mid-length, and longest sides, respectively. You are given three bits of information.
.. S +M +L = 14.5 cm
.. L = 2S
.. L = 6.2 cm
You can use an equation something like this to find the middle-length side.
.. (6.2 cm)/2 +M +6.2 cm = 14.5 cm
.. M +9.3 cm = 14.5 cm . . . . . . . . . . . . . constant terms collected
.. M = 5.2 cm . . . . . . . . . . . . . . . . . . . . . subtract 9.3 cm
Now, you know the side lengths are 3.1 cm, 5.2 cm, 6.2 cm.
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You have not offered any choices for "which equation," so take your pick of those used here.