Transcript Directed Numbers

Directed Numbers
Objective: Be able to add
and subtract directed
numbers.
First, you have to know the
8
number line!
7

If you
remember
what the
number line
looks like
you will find
this easy!
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
Let’s look at a question

Work out
What does this mean?
The first part tells
you where to start
on the number
line.
The symbols
tell you what to
do.
+6
+
-3
If they are the same,
you add.
If they are different,
you subtract
The last
number
tells you
by how
much.
Let’s do it
+6
+
-3
They are
different, so
Start here subtract… … this
much
8
7
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
One!
Two!
Three!
So there’s
your
answer, 3
+6
+
-3
=3
Here’s another …
-4
-
-9
They are the
same, so we
Start here add…
… this
much
8
7
6
5
4
3
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
So there’s
your
answer, 5