Answer:

Step-by-step explanation:
1) Rewrite
in the form
, where a = y and b = 1.

2) Use Square of Difference:
.

3) Factor
.
1 - Ask: Which two numbers add up to 6 and multiply to -7?
-1 and 7
2 - Rewrite the expression using the above.

Outcome/Result: 
4) Rewrite the expression with a common denominator.

5) Expand.

6) Collect like terms.

7) Simplify
to 

Perimeter is the sum of all outside dimensions:
5 + 3 + 1 + 2 + 4 + 5 = 20cm
Area = (5 x 5) - (2*1) = 25 - 2 = 23 cm^2
Answer:
both these equations are the examples of associative property.
#1 is the example of associative property with respect to multiplication.
#2 is the example of associative property with respect to addition.
-3x-2-6x=-4-<em>(-4x)</em>+12
-9x-2=-16x+12
7x=14
x=2.
You probably got confused with the italicized part.