Step-by-step explanation:
a= the height of the triangle=h
[tex]h^{2} = ef[/tex]
by ef, e= 18 & f=4
so...
[tex]h^{2} = 18 \times 4 = 72[/tex]
so you put both of them in a square root
[tex] \sqrt{h} = \sqrt{72}[/tex]
so the answer will be
[tex]h = \sqrt{72} = 6 \sqrt{2} [/tex]
