Question 250752
Draw an equilateral triangle and label the sides 20. Draw an altitude (height) from the top vertex to the opposite bottom side. This cuts your triangle into to halves. You have hypotenuse = 20 and one side on the bottom leg = 10. Use Pythagorean theorem to find the height.
{{{a^2 +b^2 = c^2}}}
{{{10^2 + b^2 = 20^2}}}
{{{100 + b^2 = 400}}}
{{{b^2 = 300}}}
{{{b = sqrt(300)}}}
b = 10sqrt(3).