Area of a triangle = 1/2 x Base x Height
Altitude of triangle = height of the triangle
220m2 = 1/2 x Base x 11
therefore base = 220 x 2 x 1/11
= 40 m
so base = 40m
We can crosscheck by using the formula
220 = 1/2 x 40 x 11
THEREFORE, LENGTH OF THE BASE IS 40 METERS