Without changing the number of Brain teasers and fun science tricks

Step 1: Before you three equal quadrilateral. Task: Take one match. And of the remaining three, make a new quadrilateral equal.

Step 2: Step №1

Step 3: Step №2

Step 4: Step №3

Step 5: Step №4

Step 6: Step №5

Step 7: Step №6

Step 8: Mission Accomplished!