11.4 Area of a Parallelogram

Area of Parallelograms and TrianglesParallelograms in Real Life

What is the area of this parallelogram?PARALLELOGRAMCUT HERE!S=sideH=heightB=baseWhat is the area of this parallelogram?PARALLELOGRAMMOVE TO HERE!B=baseH=heightIts the same as the area of this rectangle!PARALLELOGRAMH=heightB=baseAreaparallelogram = Base x Height(perpendicular height H)

PARALLELOGRAMB=baseSideH=heightTo find the area of a parallelogram, you always multiply the base and the height. So, Area = base x height or A = bh

Remember: The height is the line segment that is perpendicular to the base and creates a right angle.12 in10 in10 inWhat is the area of this parallelogram?Area = base x heightA = (10)(10)A = 100 inYour TurnFind the area and perimeter of the parallelogram.

24 cm 12 cmA=bhA= 12(24)A=288 cm 14 cmP = 12+12+14+14P = 52 cmExampleFind the area and perimeter of the parallelogram.

16 cm 15 cmA=bhA= 15(16)A= 240 cm 21 cmP = 15+15+21+21P = 72 cmTriangles in Real Life

Area of a Triangle12Area of parallelogram = base x heightArea of triangle = base x height

Area = bh

11Finding the Area of a TriangleWrite the formula for area of a triangle.

Substitute in values.

Simplify.11 ft23 ftA= bh

A= (23)(11)

A= 126.5 ft

You Try!Find the Area of the triangle.

A = ?, b = 16.1 ft, h = 12 ft

A= bh

A= (16.1)(12)

A= 96.6 m

A= bh

A= (9)(6)

A= 27 ft

You try!Find the area and perimeter of the triangle.

17 m13.4 m A= bh

A= (17)(13.4)

A= 113.9 m

20 m 15 m P = 20+15+17P = 52 mVideo