The temperature at the end of the day was 64 degrees. The temperature had increased twice during the day, once by 8 degrees and another time by 4 degrees. Which expression shows what the temperature was at the start of the day?
Let's denote the temperature at the start of the day as $x$.
First, the temperature increased by 8 degrees to become $x+8$.
Then, the temperature increased by 4 degrees to become $(x+8)+4$.
After both increases, the temperature was 64 degrees, so we have the equation $(x+8)+4=64$.
Simplifying the equation gives $x+12=64$, and subtracting 12 from both sides gives $x=52$.
Therefore, the expression that represents the temperature at the start of the day is $\boxed{52}$.
Let's use a variable to represent the starting temperature. Let's call it "x".
The temperature increased twice during the day, first by 8 degrees and then by 4 degrees.
So, the temperature after the first increase would be "x + 8" degrees.
And then, the temperature after the second increase would be "(x + 8) + 4" degrees.
Since the temperature at the end of the day was 64 degrees, we can set up the equation:
(x + 8) + 4 = 64
Simplifying the equation, we have:
x + 12 = 64
Subtracting 12 from both sides:
x = 52
Therefore, the starting temperature at the beginning of the day was 52 degrees.
The expression showing the temperature at the start of the day is "x", which is equal to 52 degrees.
To find the temperature at the start of the day, we need to subtract the total increase in temperature from the temperature at the end of the day.
The temperature at the end of the day is given as 64 degrees.
First, let's find the total increase in temperature by adding the increases together:
8 degrees + 4 degrees = 12 degrees
Next, we subtract the total increase from the temperature at the end of the day to find the initial temperature:
64 degrees - 12 degrees = 52 degrees
So, the expression that shows the temperature at the start of the day is 52 degrees.