Question

(please help me out D: ) (I screenshot the question and answer)

Answer 1

To find the perimeter, you need the lengths of all 3 legs,
and then you add them up.

Can you find the lengths of the other 2 sides of that triangle ?


Here are a couple of factoids I learned in 1954 and I never forgot:

In a 30°- 60°- 90°  right triangle . . .

-- the side opposite the 30° angle (the shorter leg)
    is 1/2 the length of the hypotenuse,
and
-- the side opposite the 60° angle (the longer leg)
   is (1/2 the length of the hypotenuse) times (√3).

If you have a 30°- 60°- 90° triangle and you know the length
of any one side, then you can find the lengths of the other
two sides with these amazing factoids.