Given:
Surface Area = 336 sq. inches
side lengths = 12 inches
equilateral triangles
find the slant height.
Area of an equilateral triangle = √3/4 a² = √3/4 (12in) = 62.35 in²
Perimeter = 3 a = 3 12 = 36 inches
Surface Area = Base Area + 1/2 Perimeter Slant height
336 in² = 62.35 in² + 1/2 36 in slant height
336 in² - 62.35 in² = 1/2 36 in slant height
273.65 in² 2 = 36 in slant height
547.30 in² = 36 in * slant height
547.30 in² / 36 in = slant height
15.20 in = slant height.
