Formula Isosceles Triangle Area Length of the base Height
$$A ~=~ \frac{1}{2} a \, \class{red}{h}$$ $$A ~=~ \frac{1}{2} a \, \class{red}{h}$$ $$a ~=~ \frac{2A}{\class{red}{h}}$$ $$\class{red}{h} ~=~ \frac{2A}{a}$$
Area
$$ A $$ Unit $$ \mathrm{m}^2 $$ Area of an isosceles triangle.
Length of the base
$$ a $$ Unit $$ \mathrm{m} $$ Length of the base of an isosceles triangle.
Height
$$ \class{red}{h} $$ Unit $$ \mathrm{m} $$ Height of an isosceles triangle.