Math, asked by akshityadav75, 1 year ago

Here is a Question for The Brainiest Student //___ The sides of a right angled triangle are in A.P. The area and perimeter of the triangles are numerically equal. Find it's perimeter.// No spamming otherwise reported.

Answers

Answered by Mankuthemonkey01
153
Since there are three sides in a ∆, so let the terms of A.P be

a - d, a, a + d

Here, first term = smallest side = a - d

common difference = d

So the perimeter = sum of sides
= a - d + a + a + d

= 3a


Area for right angled triangle = 1/2 × base × height.

Since, a + d would be the greatest, so it would be hypotenuse. Hence, other two sides (a -d and a) would be base and height.

So area = 1/2 × (a - d) × a

= (a - d)(a)/2

Given that perimeter = area

Perimeter = 3a

and area = (a - d)(a)/2

=>
3a =  \frac{(a - d)(a)}{2}  \\  \\  =  > a - d = 3a \times  \frac{2}{a}  \\  \\  =  > a - d = 6


Now, a + d would be equal to
 \sqrt{ {a}^{2}  + (a - d) {}^{2} }
since its a right angled triangle and a + d is hypotenuse.

=>
(a + d) {}^{2}  =  {a}^{2}  + (a - d) {}^{2}  \\  \\  =  > (a + d) {}^{2}  =  {a}^{2}  + 6 {}^{2}  \\  \\  =  > (a - d) {}^{2}  + 4ad =  {a}^{2}  + 36 \\  \\  =  > 36 + 4ad =  {a}^{2}  + 36 \\  \\  =  > 4ad =  {a}^{2}  \\  \\  =  > 4d = a

[ Since,

(a + d)² = (a - d)² + 4ad

and, (a - d) = 6

=> (a - d)² = 36 ]

So we have

a - d = 6

and 4d = a

So put the value of a

=> 4d - d = 6

=> 3d = 6

=> d = 6/3

=> d = 2

So a - d = 6

=> a - 2 = 6

=> a = 6 + 2

=> a = 8

So perimeter = 3a = 3(8) = 24


Answer :- 24


Hope you understand

Mankuthemonkey01: Thank you all
tanishq972003: hey how (a+d)^2=(a-d)^2-4ad?
tanishq972003: see in answer when they put Pythagoras theorm
tanishq972003: thanks not I get it
tanishq972003: now*
Answered by UltimateMasTerMind
128
______Heyy Buddy ❤______

____Here's your Answer_______

Let the sides be a-b , a, and a + b with a + b as the Hypotenuse.

Therefore,

PERIMETER of TRIANGLE = (a- b) + a + (a +b)

=> a - b + a + a + b

=> 3a.-------------(1)

Now, Since it is a right angle triangle.

Therefore,

Area of Triangle = 1/2 × Base × Height

=> 1/2 × (a) × (a-b)

=> [ a( a - b)]/2 -----------(2)


A.T.Q.

PERIMETER = AREA

=> 3a = [ a ( a - b)] /2

=> 3a × 2 = a ( a - b)

=> [3a × 2] / a = a- b

=> 6 = a - b. ----------(3)

Now,

By Pythagoras Theorem,

 =  >  \:  {(a + d)}^{2}  =  {a}^{2}  +  {(a - b)}^{2}

Putting eq 3 here, we get...

 =  >  \:  {(a + d)}^{2}  =  {a}^{2}  +  {6}^{2}
Here, ( a + b)^2 = (a-b)^2 + 4ab

=> ( a - b)^2 + 4ab = a^2 + 36

=> putting eq 3.

=> 36 + 4ab = a^2 + 36

=> 4ab = a^2

=> 4ab/a = a

=> a = 4b.

Now,

a - b = 6

=> 4b - b = 6

=> 3b = 6

=> b = 2.

Putting b = 2 in eq 3. we get,

=> 6 = a - b

=> 6 = a - 2

=> a = 8.

Therefore, side of the triangle = 8.

Now,

PERIMETER of TRIANGLE = 3 × sides ( from eq 1)

=> PERIMETER = 3 × 8

=> PERIMETER = 24cm.
✔✔✔✔

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thakurgeetanjalihmr: what is your real name????
ps08062014: hey mr. brainly expert can I know ur real name pls...
ps08062014: hey mr.ultimatemastermind pls..
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