Answer:
x = 13 − 2 = 11
∘
F
Step-by-step explanation:
Let the original temperature be
I = x
.
Final temperature
F = − 2
∘
Change in temperature
C = I − F = x − (
−
2
) = ( x +
2
)
∘
F
But it’s given change in temperature
C = 13
∘
F
Therefore,
C = 13 = ( x + 2
)
∴ x +
2 = 13 or x = 13 −
2 = 11
∘
F
-------------------------------------------------------------------------------------------------
Explanation:
Another way to approach this question, without algebra, is to approach it this way:
We know that at the end of the time period, it's −
2
∘
F. At the beginning of the time period, it was
13
∘
F warmer. And so we can say that the temperature at the beginning of the time period can be found by adding −
2 and 13
:
−
2
+
13
=
11
∘
F
