Area and volume help?

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2 Answers
Feb 16, 2018

Area A=42

Explanation:

In the figure, we can split the given closed polygon into rectangles and triangles

Triangles are 4 in number

b1=3,h1=2,T1=12(b1h1)=12(3)(2)=3
b2=4,h2=2,T2=12(b2h2)=12(4)(2)=4
b3=3,h3=2,T1=12(b1h1)=12(3)(2)=3
b4=4,h4=2,T1=12(b1h1)=12(4)(2)=4

Total area of triangles T=T1+T2+T3+T4
T=3+4+3+4=14

Rectangle is 1 in number

b=7,h=4,R=b1h1=(7)(4)=28

Total area A=T+R=14+28=42

Area A=42

Feb 16, 2018

area =42 square units

Explanation:

we can split the figure into 'regular' figures

the central region is a rectangle

the regions above and below the rectangle are triangles

area of rectangle =length × breadth

area of triangle =12× base × height

area of rectangle =7×4=28

area of 2 congruent triangles =2×12×7×2=14

area of figure =28+14=42 square units