Question

The sides of a triangle are 3x + y −4z ; x + 2y −3z ; x – y + 5z . Find the perimeter of the triangle.


pls tell the answer . this for class 7 . my sister's question . pls she need the answer .
the first correct answer will be marked as brainlist​

Answer 1

Answer:

Let a=3x+4y,b=4x+3y and c=5x+5y be the largest side

⇒cosC=

2ab

a

2

+b

2

−c

2

=

2(3x+4y)(4x+3y)

(3x+4y)

2

+(4x+3y)

2

−(5x+5y)

2

⇒cosC=

2(3x+4y)(4x+3y)

9x

2

+16y

2

+24xy+16x

2

+9y

2

+24xy−25x

2

−25y

2

−50xy

<0,x,y>0

⇒cosC=

2(3x+4y)(4x+3y)

−2xy

<0,x,y>0

⇒θ>90

∘

∴, the triangle is obtuse angled.

Step-by-step explanation:

pls dear make me brain list

Answer 2

sides of triangle =

$(3x + y - 4z) \: , (x + 2y - 3z) \: , (x - y + 5z).$

perimeter of triangle =

$a + b + c.$

now ,

$(3x + y −4z ) + (x + 2y −3z) + ( x – y + 5z) . \\ 3x + y - 4z + x + 2y - 3z + x - y + 5z \\ 3x + x + x + y + 2y - y - 4z + 3z + 5z \\ 5x + 2y + 4z.$

so , perimeter of triangle is

$5x + 2y + 4z.$

hopefully its helped u dear :)