Question

The perimeter of an equilateral triangle is 9 cm so its altitude will be​

Answer 1

Answer:

let the side of the triangle be a

perimeter =3a

9=3a

a=3

altitude drawn from an equilateral triangle bisects the opp side

therefore

altitude²=1.5²+3²

altitude ²=2.25+9

altitude ²=11.25

therefore

altitude =root11.25

Answer 2

Answer:

$15\sqrt{3}$

Step-by-step explanation:

If the perimeter is 9cm. each side is 3 cm each.

Since the altitude of an equilateral triangle bisect the opp side., it will be 1.5cm.

by Pythagoras

$3^{2}= 1.5^{2} +x^{2}$

$9-2.25=x^{2}$

$x^{2} =6.75$

$x=15\sqrt{3}$

$=25.98 cm$