March 15th, 2012, Aim: How do you find the area of PARALLELOGRAMS and TRAPEZOIDS ? ? ?

         

PARALLELOGRAMS AND TRAPEZOIDS !!!

~ WE HAVE LEARNED TO FIND THE AREAS OF TRIANGLES AND RECTANGLES, NOW ITS TIME TO FIND THE AREAS OF PARALLELOGRAMS AND TRAPEZOIDS !

 

NOW TO FIND THE AREA OF PARALLELOGRAM IS THE SAME WAY AS TRIANGLES AND RECTANGLES.... 

AREA= BASE * HEIGHT

EXAMPLE :

• A= B* H
• A= 9*4
• A= 36 in^2

                       

 

     

                                                                     

• A= B*H
• A=10.3*6.2
• A= 63.86 cm^2

 ~ NOW YOU GIVE IT A TRY !

 

(1) If b is the base and h is the height of the parallelogram,
find the area when b = 6  units and h = 11 units:

1.  17
2. 66
3. 5

 (2) If the base is 7.25 and the height is 8 of the parallelogram then what is the AREA ?

1. 15.25
2. 56
3. 58

     WRITE ANSWERS WITH NUMBERS IN COMMENTS BELOW !

~ NOW TO FIND THE AREA OF TRAPEZOIDS IS NOT AS SIMPLE AS FINDING THE AREAS OF TRIANGLES, RECTANGLES, AND PARALLELOGRAMS, BUT YOU CAN DO IT !

 

THE FORMULA TO FIND THE AREA OF A TRAPEZOID IS . . .   AREA = 1/ 2* H* (B1+B2).

 

 TO MAKE IT EASIER FOR YOU FOLLOW THESE STEPS :

1. ADD THE FIRST AND SECOND BASE (B1+B2)
2. THEN DIVIDE THE SOLUTION BY  2
3. WHEN YOU HAVE THAT SOLUTION MULTIPLY IT BY THE HEIGHT (H)

EXAMPLE :

 STEPS: 

(B1+B2) PLUG IT IN --> ( 6+2)

(6+2) = SOULTION (8) THEN DIVIDE IT BY 2 --> 8/2 =4

4 IS THE SOULUTION , SO MULTIPLY IT BY THE HEIGHT (H)

ANSWER = 16

NOW YOU TRY IT !  
                                                

	GOOD LUCK!!!

   3. If b₁ is the top base, b₂ is the bottom base, and h is the height of the trapezoid, find the AREA when b₁ = 17 units, b₂ = 19 units, and h = 4 units:
 

   4. If b₁ is the top base, b₂ is the bottom base, and h is the height of the trapezoid, find the AREA when b₁ = 3 units, b₂ = 7 units, and h = 2 units:

 

 WRITE ANSWERS WITH NUMBERS IN COMMENTS BELOW !

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