EQL triangle

Calculate inradius and circumradius of equilateral triangle with side a=77 cm.

Correct result:

r1 =  22.2 cm
r2 =  44.5 cm

Solution:

 tan30=r1772 r1=772tan30=22.2 cm \ \\ \tan 30 ^\circ = \dfrac{ r_1 }{ \dfrac{ 77}{2 } } \ \\ r_1= \dfrac{ 77}{2 } \tan 30 ^\circ = 22.2 \ \text{cm}
 cos30=772r2 r2=772/cos30=44.5 cm \ \\ \cos 30 ^\circ = \dfrac{ \dfrac{ 77}{2 } }{ r_2 } \ \\ r_2= \dfrac{ 77}{2 } / \cos 30 ^\circ = 44.5 \ \text{cm}

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Pythagorean theorem is the base for the right triangle calculator.
See also our trigonometric triangle calculator.

 
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