Knowing Your Basic Facts 
Can Help You Figure Out 
Numeric Expressions.

  +    = 

If is a 3, and is a 5
then must equal an 8

3 + 5 = 8

  ^-    = 

If is a 6, 
and  is a 4
What does equal ?
Well, 6 - 4 = 2, So equals 2.

6 - 4 = 2

Try These:
Example 1:

+    = 
If = 7
 and = 11,
what is the missing addend for ?
(Think: 7 + ? = 11)
7 + 4 = 11
so the missing addend for is 4

Example 2:

x =
If  = 5
and = 3,
what is the missing product for ? 
(Think: 5 x 3 = ?)
5 x 3 = 15
so the missing product for is 15