Question

Area of a right angled triangle is 54 cm square.
if one of its leg is 12cm long then what will be the perimeter?

Answer 1

area equals 54cm
1/2×base ×height=54
base =54/6=9
perimeter =sum of 3 sides
3rd side =√9^2+12^2
3rd side =15
perimeter= 15+9+12=36

Answer 2

Area of right angled triangle

= 1/2 × base × height = 54

Taking base as 12 cm we get

1/2 × 12 × height = 54

=> 6 × height = 54

=> height = 54/6

=> height = 9 cm


So we have its two sides as 12cm and 9cm

Now we will have to find the hypotenuse to find the perimeter of the figure.

=> Hypotenuse² = base² + height²

=> Hypotenuse² = 12² + 9²

=> Hypotenuse² = 144 + 81

=> Hypotenuse² = 225

=> Hypotenuse = √225

=> Hypotenuse = 15 cm

So the perimeter = sum of all sides.

=> Perimeter = 12 + 9 + 15

=> Perimeter = 36 cm




Answer :- 36 cm