Step by step
The question
Question: It is −2°C.
It gets 5 degrees colder.
What is the temperature now?
1 Write it as a sum
We start at −2.
Colder means down: take away 5.
−2 − 5
Below zero is negative.
−2°C: below zero
colder 5 → − 5
2 Work it out
Start at −2.
Go down 5.
Careful!
Colder from below zero goes further down.
The number gets more negative.
Careful: not −2 − 5 = 3 ✗
We land on −7°C.
= −7°C
So the answer is −7°C: 7 degrees below zero.
3 Check
Let's check: go back.
−7 plus 5 is −2, where we started.
So the answer is right!
−7 + 5 = −2
Let's look back.
First: write it as a sum.
Then: work it out.
Last: check.
Answer
= −7°C