Answer:
Subtraction property of equality.
Answer:
second choice
Step-by-step explanation:
Recall that the equation to find the perimeter of a rectangle is 2(L + w)
Since we know the length, we can make an equation:
2(3 + w) = 12
Divide both sides by 2:
(3 + w) = 6
w = 3
Now that we know both length and width, we simply have to find their product to solve for area:
a = L * w
a = 3 * 3
a = 9
The area of the rectangle is 9 cm^2.