3. Write an equation, using variables, to represent the identities we der
4. Using your knowledge of identities, fill in each of the blanks.
a. 4+5- = 4
b. 25 + 10 = 25
_+16-16 = 45
d. 56-20+ 20 =_____
5. Using your knowledge of identities, fill in each of the blanks.
a. a+b-
=a
d.
-=
b. c-d+d=_
c. e+-f=e
_-h+h=g