Respuesta :

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.

This is what we know so far.

Perimeter: 12cm

Rectangle Length: 3cm

Theoretically speaking if one side is 3cm (it's a rectangle not a square)

then it cannot be 3cm on all sides because that would be a square.

If it was 3cm on all sides the area would be 9cm. Because it is a rectangle one side would be 3cm and the other 4cm. (12÷3=4)

Answer:

The area is 12 cm.

Equation: 3 ×. 4 = 12cm

Formula: length × width