Question

Please answer all four questions..
Please...

Answer 1

GIVEN THAT,

Area of Equilateral traingle = 4√3 cm²

\begin{lgathered}\frac{ \sqrt{3} }{4} \times (side) {}^{2} = 4 \sqrt{3 } \\ \\ {(side)}^{2} = 4 \sqrt{ 3} \times \frac{4}{ \sqrt{ 3 } } \\ \\ {(side)}^{2} = 4 \times 4 \\ \\ (side) {}^{2} = (4)^2 \\ \\ = > side = 4 \: cm\end{lgathered}43​​×(side)2=43​(side)2=43​×3​4​(side)2=4×4(side)2=(4)2=>side=4cm​ 

HENCE,

Length of side of given equilateral triangle is 4 cm

Answer 2

13. perimeter of equilateral triangle = √3/4^2

√3/4^2×(4√3)
= √3/4×4√3×4√3
= √3/4×16×3
= √3×12
= √36
= 6 cm

14. sides of the triangular field are :
30m , 72m , 78m
= 30:72:78
= 5:12:13

so, the triangle is right angle.
AB= 30m
BC= 72m
AC=78m

= 1/2×30×72= 1/2× altitude×72

altitude = 30m