So for the first one it is (x-3)(x+3) this is because it is a difference of squares so you square root the 9 and the minus you do both +and - in order to keep up the -9
The zeros are:x=3 and x=-3 ( this is because you change the sign in the bracket
the others should be pretty simple to do for number 2 its a complex
the third is a simple trinomial
and fourth is simple trinomial as well
Answer:

Step-by-step explanation:

Answer:
C
Step-by-step explanation:
-5.5-11.2
change the subtraction to addition
5.5+11.2= 16.7
Answer:
Square shaped = 27 cubic inches , Rectangular shaped = 3LW cubic Inches
Step-by-step explanation:
If the dictionary is a square ( all sides are equal ) the the volume is
V = Length * Length * Length = 
V = 3 * 3 * 3 = 27 
while if its rectangular ( all side are not equal ) shaped
V = Length * Width * Height (thickness)
V = L * W * 3 = 3LW 
Answer:
11in
Step-by-step explanation:
a^2+b^2=c^2 when c is the hypotenuse
10^2+sqrt21^2=c^2
100+21=c^2
121=c^2
11=c