Question

Assertion: The sides of a triangle are in the ratio of 3: 4: 5 and its perimeter is 144cm. The area of the triangle is 864cm2

Reason: Perimeter of a triangle = a + b + c, where a,b,c are sides of a triangle.

Both assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of assertion (A)
Both assertion (A) and Reason (R) are true but reason (R) is not the correct explanation of assertion (A)
Assertion (A) is true but reason (R) is false
Assertion (A) is false but reason (R) is true
pls answer it fast.

Answer 1

Step-by-step explanation:

Let the sides of triangles are 3x,4x and 5x.

And perimeter of the triangle is 144cm.

So , 3x+4x+5x=144

12x=144

x=12

so, the sides are triangle are 3(12)=36cm, 4(12)=48cm , 5(12)=60cm

so , the longest side is 60 cm.

Area of triangle =

s(s−a)(s−b)(s−c)

here , s=72 and a=36, b=48 c=60

=

72(72−36)(72−48)(72−60)

=

72(36)(24)(12)

=

746496

= 864

So, the area of triangle is 864 cm

2

and the height corresponding to longest side h=

60

2×864

=28.8cm

Answer 2

Answer:

Both assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of assertion (A)