Saved Bookmarks
| 1. |
15 mare 12.1018 cm 3IR 10 c42 cm |
|
Answer» 1)Given,Side a=18cmSide b=10cmPerimeter=42cm=a+b+c:. Putting value42=18+10+c42=28+c42-28=c14=cNow,S=(a+b+c)/2:. Putting valueS=42/2S=21Now according to Heron's formula-Area of a triangle=√{s(s-a)(s-b)(s-c)}:. Putting value=√{21(21-18)(21-10)(21-14)}=√{21(3)(11)(7)}=√4851=21√11cm² 2)Let the sides be 12x,17x and 25x.now perimeter=540cmso 12x+17x+25x=54054x=540xx=10so the sides are 120,170,250 s(semi perimeter )=perimeter/2s=540/2s=270 area of scalene triangle=√s×(s-a)×(s-b)×(s-c). where a, b, c are the sidesarea=√270×150×100×20=√2×3×3×3×5×2×5×3×5×2×5×2×5×2×2×5=2×3×5×3×5×2×5×2=9000cm^2 |
|