Square units of length. The exact units will depend on the size of the object:
A screen pixel may be measured in square millimetres, a postage stamp in square centimetres, a wall in square metres, city blocks in square kilometres.
28 units
The area of a rectangle is (length) multiplied by (width). The units don't matter. Just make sure that 'length' and 'width' are both measured in the same unit, whatever the unit is.
6 units long and 5 units wide
42 <insert unit> squared.
Yes, the rectangle is one unit wide, and twenty units long. there are probably others, too.
28 units
The area of a rectangle is (length) multiplied by (width). The units don't matter. Just make sure that 'length' and 'width' are both measured in the same unit, whatever the unit is.
Acre is an unit of area and thus cannot represent sides of a rectangle
6 units long and 5 units wide
...
Rectangle area = (rectangle width) x (rectangle height)
42 <insert unit> squared.
Yes, the rectangle is one unit wide, and twenty units long. there are probably others, too.
315 square unitsThe area of a rectangle is measrure through its length multiplied by its height orArea= length x widthsoArea= 21 x 15= 315 square units (if it had a unit like cm or km, replace unit with that)
A = lw Area of a rectangle = length times width
The area of the rectangle formed in this way is 5 x 4 = 20 sq units (no unit of measurement has been provided).
Perimeter is a unit of length. Area is a unit of area. The two units are not directly convertible.However, the area of a rectangle is length times width, and the perimeter is two times length plus two times width. Given constant perimeter, a square has maximum area, while a very thin rectangle has nearly zero area. (In calculus terms, the limit of the area as length or width goes to zero is zero.)Depending on how you want to name your units, you can always find a rectangle whose perimeter is "larger" than area, but this is a numerical trick that is not valid in any school of thought of mathematics that I know.