Do you know the formula for the area of a triangle ?
Pick a base-length and a height for your triangle so that 1/2 (base x height) = 20.
Do you know the formula for the area of a parallelogram ?
Pick a base-length and a height for your parallelogram so that (base x height) = 20.
We're having a problem understanding your difficulty.
Of course, if you don't know the formulas for area . . .
draw a parallelogram which is not a rectangle.verify that its area is equal to the rectangle on the same base and altitude
You can't without having incomplete units.
== == 1) Draw a line segment AB of 5 units 2) Draw the perpendicular bisector CD of AB such that Cd meerts AB at C. 3) Mark off CE = 2 units on CD 4) Draw the straight line segments AE & BE. ABE is your triangle. Its base (AB) = 5 and height (CE) = 2, so its area = [base x ht] / 2 = 5 sq units
You don't have to do anything at all. As soon as you draw a triangle, it automaticallyhas area. The only trick for you is to figure out how much area it has.
Draw a right angled triangle with legs of 4cm and 6cm
An equilateral triangle with sides of 10/3 units, an isosceles triangle with 2 sides of a units and the third of 10-2a units (for any a<5), or several options for scalene triangles. A square or rhombus with sides of 2.5 units, or a rectangle or parallelogram with sides of b and 5-b units etc A regular pentagon with sides of 2 units. And so on.
Draw a straight line AB of any length x. Draw another line, parallel to AB and at a distance of 2*24/x units from it. Select any point on the second line and call that point C. Join AC and BC. Then triangle ABC will have an area of 24 square units.
Draw a right angled triangle with legs of lengths 2 and 3 units. The hypotenuse will be sqrt(13) units.
Squares are rectangles. Draw a 2 unit square.
First draw a rectangle with an area of 6 square units - for example 2 units x 3 units. Then "slide" the topmost side along its length through any distance of your choice. (You could slide any side along its own length.) The length of the base has not been altered and, since the top was slid along its length, the vertical height has not been changed either. So the area remains unchanged at 6 sq units.