1. The base and the height of the Parallelogram

2. √ √ Which is the parallelogram? And how can you confirm it?
(1) (2) (3) (4) √ √

3. A parallelogram has two groups of parallel opposite sides .
In a parallelogram, the opposite sides are with the same length and the opposite angles are equal .

4. A B C D
height
base E
From any point on one side, we draw a perpendicular line segment toward the opposite side. The perpendicular line segment is the height of this parallelogram.

5. Pointed out the base and the height which are relative.F
From any vertex, we can draw two heights on this parallelogram.

6. Can you try to draw the height to base-BC in the parallelogram?
Steps:
① Put a set square on the base-BC.
② Move the ruler to choose a
point of the opposite side.
③ Draw a line segment from the
point to base-BC. A B C D

7. Draw the height from vertex DB C D E E
base
base

8. Draw the height from vertex DB C D
base E

9. Draw height according to the base

10. Draw parallelograms (At least two parallelograms) Requirement:
Draw the parallelograms which length of base is 4cm and the length of height is 3cm.

11. Choice
In the parallelogram ABCD, AB＝6cm, BC＝8cm, then AE maybe equal to ( ) cm A A B C D E
(A) (B) (C) 7
In a right-angled triangle, hypotenuse is the longest.

12. Choice
In the parallelogram ABCD, the perimeter is e 50cm, AB＝15cm, then BC＝ ( ) cm B A B C D E
(A) (B) (C) 20
50 ÷ 2－15＝10 (cm)