Answer:
It is one-half the area of a rectangle of length 4 units and width 3 units.
Explanation:
Base of triangle = 4 units.
Height of triangle = 3 units
Formula of area of triangle :

So, the area of the given triangle =

=

=

Option 1: It is twice the area of a rectangle of length 4 units and width 3 units.
Area of rectangle :

=

=

Area of triangle is 6 square units
Area of rectangle is 12 square units


So, area of triangle is half the area of rectangle of length 4 units and width 3 units. .
Hence Option 1 is wrong .
Option 2: It is twice the area of a square of side length 3 units.
Area of square =

=

=

Area of triangle is 6 square units.
Area of square is 9 square units .


So, area of triangle is not twice the area the area of a square of side length 3 units.
Hence Option 2 is wrong .
Option 3: It is one-half the area of a rectangle of length 4 units and width 3 units.
Area of rectangle :

=

=

Area of triangle is 6 square units
Area of rectangle is 12 square units


So, area of triangle is half the area of rectangle of length 4 units and width 3 units.
Hence Option 3 is right.
Option 4 : It is one-half the area of a square of side length 3 units.
Area of square =

=

=

Area of triangle is 6 square units.
Area of square is 9 square units .


Hence Option 4 is wrong .
Hence Option 3 is correct :It is one-half the area of a rectangle of length 4 units and width 3 units.