It's base is 6m and altitude is 3m.
Step by Step Explanation.
Let the altitude(h) and base(b) of the triangle be x m and 2x m respectively.
Area(A)= 9 m^2
We know,
A=1/2*b*h
or, 9= 1/2*2x*x
or, 9*2= 2x^2
or, 18= 2x^2
or, 18/2 = x^2
or, 9 = x^2
or, 3^2= x^2
so, x = 3 m
Hence, altitude =x= 3m
and, base = 2x=2*3= 6 m
