Question

the area of an isosceles triangle is 216 cm2 if one of its equal sides is 30 cm find its base

Answer 1

Area of isosceles triangle =

$1 \div 2 \times 30 \times base = 216 \\ \\ 15 \times base = 216 \\ \\ base = 216 \div 15 \\ \\ base = 14.4$

Answer 2

216 = 1/2 * base * height

216 = 1/2 * base * 30

216/15 = base

14.4 = base