## lyzkhalifaa Group Title if an equillateral triangke has the perimeter of 66, what is the altitude? i just wanna know how to solve it, like the formula. one year ago one year ago

1. Hero Group Title

Well, if given the perimeter of an equilateral triangle, you can find the lengths of the sides by using the formula $S_{\text{Triangle}} = \frac{P}{3}$ |dw:1357829776184:dw| Afterwards, you'll have to draw the altitude which divides the base of the triangle in half. |dw:1357829954412:dw| Furthermore, you'd have to use Pythagorean Theorem to find the the length of the altitude

2. lyzkhalifaa Group Title

|dw:1357830348662:dw| so, how would i make this into a pythagoream theorom?

3. Hero Group Title

Split the bigger triangle into two smaller ones. Then just solve for one of the missing sides. The missing side is the altitude of course.

4. Hero Group Title

|dw:1357830687072:dw| a^2 + b^2 = c^2 a^2 + 11^2 = 22^2

5. lyzkhalifaa Group Title

i got a=24.6 .. is that right?

6. Hero Group Title

c = 22 is the hypotenuse, right? So either leg has to be less than that. In other words a < c

7. Hero Group Title

So there's no way that a = 24. 6

8. lyzkhalifaa Group Title

11x11=121 and 22x22=484, then i added them together and 605 and the squareroot of 605 was 24.6 :c

9. Hero Group Title

a^2 + 11^2 = 22^2 a^2 = 22^2 - 11^2 a^2 = 484 - 121

10. lyzkhalifaa Group Title

i got 11$\sqrt{3}$

11. lyzkhalifaa Group Title

with the 11 infront

12. lyzkhalifaa Group Title

thank you Hero (:

13. Hero Group Title

a^2 + 11^2 = 22^2 a^2 = 22^2 - 11^2 a^2 = 484 - 121 a^2 =121(4 - 1) a^2 = 121(3) a = sqrt(121*3) a = sqrt(11^2)sqrt(3) a = 11sqrt(3)