30:60:90 small triangle
12 root 3 : 12 : 24 root 3
What I get is the side of the big equilateral triangle is 24 root 3 + 12
Geometry
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side of square=12
In the bottom left, a right angled triangle is formed. with base angle 60 degree and another base angle 90 degree
thus tan 60 = 12/base side ->base side = 12/root(3) = 4*root(3)
similarly base side of bottom right = 4*root 3.
Side of triangle = 12+4*root (3)+4*root (3) = 12 + 8*root(3)
perimeter = 3*side = 36 + 24*root(3)
IMO D
In the bottom left, a right angled triangle is formed. with base angle 60 degree and another base angle 90 degree
thus tan 60 = 12/base side ->base side = 12/root(3) = 4*root(3)
similarly base side of bottom right = 4*root 3.
Side of triangle = 12+4*root (3)+4*root (3) = 12 + 8*root(3)
perimeter = 3*side = 36 + 24*root(3)
IMO D
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I'm gonna rule this test
Thanks
So
it's 30:60:90
12/root3 : 12 : 24/root 3
4 root 3 : 12 : 8 root 3
Side of equi triangle = 4 root 3 + 12 + 4 root 3
= 8 root 3 + 12
* 3
24 root 3 + 36
Thanks
So
it's 30:60:90
12/root3 : 12 : 24/root 3
4 root 3 : 12 : 8 root 3
Side of equi triangle = 4 root 3 + 12 + 4 root 3
= 8 root 3 + 12
* 3
24 root 3 + 36
30:60:90 triangle sides conform to ratio x : x.√3 : 2x
=> x.√3 = 12
=> 2x = 12/√3 . 2 = 8√3
So the length of the side of the triangle = 12 + 8√3
=> perimeter = 3(12+8√3) = 36 + 24√3
Sometimes using a/Sin A = b/Sin B = c/Sin C also helps finding sides from angles if we don't remember the 30:60:90 formula.
=> x.√3 = 12
=> 2x = 12/√3 . 2 = 8√3
So the length of the side of the triangle = 12 + 8√3
=> perimeter = 3(12+8√3) = 36 + 24√3
Sometimes using a/Sin A = b/Sin B = c/Sin C also helps finding sides from angles if we don't remember the 30:60:90 formula.
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Hi,
30:60:90 triangle sides are in the ratio, x: x√3:2x
so x√3=12 base of the right triangle ---> base of the equilateral triangle= 2(12/√3)+side of square i.e 12
simplifying we get value as 8√3+12.
perimeter of equilateral triangle=3*(8√3+12)---hence ans D
30:60:90 triangle sides are in the ratio, x: x√3:2x
so x√3=12 base of the right triangle ---> base of the equilateral triangle= 2(12/√3)+side of square i.e 12
simplifying we get value as 8√3+12.
perimeter of equilateral triangle=3*(8√3+12)---hence ans D