Question

The temperature of a city doubles during the day, and then decreases by 1.4 degrees after the sun goes down. The temperature at the end of the day is -1.7 degrees What was the temperature of the beginning of the day

Answer 1

Let's assume the temperature at the beginning of the day is x degrees.

Since the temperature doubles during the day, the temperature becomes 2x degrees.

After the sun goes down, the temperature decreases by 1.4 degrees, so the temperature becomes 2x - 1.4 degrees.

Given that the temperature at the end of the day is -1.7 degrees, we can set up the equation:

2x - 1.4 = -1.7

Adding 1.4 to both sides of the equation:

2x = -1.7 + 1.4

2x = -0.3

Dividing both sides of the equation by 2:

x = -0.3/2

x = -0.15

Therefore, the temperature at the beginning of the day was -0.15 degrees.