English, asked by nimishgowda123, 5 months ago

if
AB=3
EB=7
CA=4
then AC=?​

Answers

Answered by Anonymous
1

Answer:

Explanation:

BD=DE=EC=  

3

5

​  

 and △ABC is a right angled triangle.

Now  

cosC=  

2.AC.EC

AC  

2

+EC  

2

−AE  

2

 

​  

 

Or  

AE  

2

=AC  

2

+EC  

2

−2.AC.EC.cosC

Or

=4  

2

+(  

3

5

​  

)  

2

−2.8.  

3

5

​  

.cosC

=16+  

9

25

​  

−  

3

2×4×5

​  

.  

5

4

​  

 

Or

=  

9

169

​  

−  

3

32

​  

 

=  

9

169−96

​  

 

=  

9

73

​  

.

Hence

AE  

2

=  

9

73

​  

.

cosθ=  

2.AE.4

AE  

2

+4  

2

−  

3

5

​  

 

2

 

​  

 

=  

73

​  

 

8

​  

.

Hence

secθ=  

8

73

​  

 

​  

 

Now  

tanθ=  

sec  

2

θ−1

​  

 

=  

64

73

​  

−1

​  

 

=  

8

3

​  

.

Answered by deventanna23
0
By Pythagoras Theorem,
⇒ AC2 = AB2+ BC2
Given in ΔABC, AB = 3, BC = 4, AC = 5.
⇒ 52 = 32 + 42
⇒ 25 = 25
∴ ΔABC is a right angled triangle and ∠B is a right angle.
We know that the radius of the circle touching all the sides is (AB + BC – AC )/ 2
⇒ The required radius of circle = (3 + 4 – 5 )/2 = 2/2 = 1
I hope you get your answer
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