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HOW DO I FIND THE AREA OF DEF?

HOW DO I FIND THE AREA OF DEF?-example-1

2 Answers

5 votes

Answer:

≈169.7

Explanation:

cos30 = (7
√(3))/x

x= (7
√(3))/cos30 = 14

h = 14+14 = 28

sin30 = EF/28

EF = sin30 * 28 = 14

tan30 = 14/DF

DF = 14/tan30 ≈ 24.248

Area = 24.248*14/2 ≈ 169.74 ≈ 169.7

User Kaushik Shankar
by
4.1k points
4 votes

Answer:

169.7

Explanation:

first lets find the other side of the small triangle

cos(30 degrees)=(7*sqrt (3))/x

x*cos(30 degrees)=7*sqrt (3)

x=(7*sqrt (3))/cos(30 degrees)

x=14

14/14=1

so proportion is 1/1

thus the bottom the outer part of the triangle is also 7*sqrt(3)

now, for the area

lets find the 2 side length of the triangle we need

DE: 14+14=28

DF: 7*sqrt(3)+7*sqrt(3)=14*sqrt(3)

let's find EF,

sin(30 degrees)=x/28

x/28=sin( 30 degrees)

x=28*sin( 30 degrees)

x=14

A=(14*sqrt(3))*14*0.5

A=(14*sqrt(3))*7

A= around 169.7

User TeAmEr
by
3.7k points