## Altair how do i determine the height of a triangle with only the length nd sides? 2 years ago 2 years ago

1. Altair

The base of the tent measures 96 inches wide, and the length from the top point of the tent to the corners of the base is 102 inches.

2. Altair

What is the length of the pole that Daniel needs to support the middle of the tent?

3. Zara

Use pythagoras' theorem :)

4. Altair

how do u suppose i do dat?

5. Zara

imagine a line from the top point to the middle of the base. You now have two right angled triangles. Use pythagoras' theorem on one to find the height (the line you've drawn in) a^2+b^2=c^2 a=96/2=48 b=the height c=102 48^2+b^2=102^2 2304+b^2=10404 b^2=10404-2304=8100 b=sqrt(8100) b=90

6. Altair

A. 72 inches B. 180 inches C. 96 inches D. 90 inches

7. Zara

b=90, so b is answer D! Do you understand it?

8. Altair

9. Zara

use pythagoras' theorem again. in this case: a=sqrt(40) b=3 c=z on the diagram so: sqrt(40)^2+3^2=c^2 40+9=c^2 49=c^2 c=sqrt(49) c=7 :)

10. Altair

11. Zara

are you actually understanding this or just taking the answers? if you're learning you should be able to work this out now. remember, for right angled triangles, just use pythagoras' theorem!

12. Zara

you there?

13. Altair

im having trouble with the squareroot part

14. Zara

what exactly do you mean? :)

15. Altair

$\sqrt{15}$

16. Zara

are you doing the question you attached? how does the sqrt(15) come into it?

17. Altair

im doing em i just dont understand em

18. Zara

so you are doing the attached one? do you know pythagoras' theorem?

19. Altair

yes and yes a^2+b^2=c^2

20. Zara

correct :) in this case you need to find a, so rearrange the equation so that a is by itself

21. Altair

but the square root how do i figure that

22. Zara

when you rearrange, the equation is: a^2=c^2-b^2 i think you mean sqrt(53)=z? In pythagoras' theorem, the z is the equivalent of c because it is the hypotenuse, so you subsitute this into the equation: a^2=sqrt(53)^2-b^2 when you square a square root, you're basically just getting rid of the square root, so sqrt(53)^2=53 does that help?

23. Altair

yes

24. Zara

good, so you can answer the question now? :)