HERON's FORMULA3. There is a slide in a park. One of its side walls ha

1.	HERON's FORMULA3. There is a slide in a park. One of its side walls has been painted in some colour with amessage "KEEPTHE PARK GREEN AND CLEAN" (see Fig. 12.10). If the sides of thewall are 15 m, 11 m and 6 m, find the area painted in colour.KEEP THE PARKGREEN AND CLEAN11 m15 m
Answer» Let the Sides of the triangular wall are a=15 m, b=11 m & c=6 m. Semi Perimeter of the ∆,s = (a+b+c) /2 Semi perimeter of triangular wall (s) = (15 + 11 + 6)/2 m = 16 m Using heron’s formula, Area of the wall = √s (s-a) (s-b) (s-c) = √16(16 – 15) (16 – 11) (16 – 6) = √16 × 1 × 5 × 10 = √ 4×4×5×5×2 = 4×5√2 = 20√2 m²

HERON's FORMULA3. There is a slide in a park. One of its side walls has been painted in some colour with amessage "KEEPTHE PARK GREEN AND CLEAN" (see Fig. 12.10). If the sides of thewall are 15 m, 11 m and 6 m, find the area painted in colour.KEEP THE PARKGREEN AND CLEAN11 m15 m

Answer»

Let the Sides of the triangular wall are a=15 m, b=11 m & c=6 m.

Semi Perimeter of the ∆,s = (a+b+c) /2

Semi perimeter of triangular wall (s) = (15 + 11 + 6)/2 m = 16 m

Using heron’s formula, Area of the wall = √s (s-a) (s-b) (s-c)

= √16(16 – 15) (16 – 11) (16 – 6)

= √16 × 1 × 5 × 10 = √ 4×4×5×5×2 = 4×5√2

= 20√2 m²