Let ABC be the triangle (with A as summit) and BC its base which is at the same time the diameter of the semi-circle. Let AH be the altitude of ABC.
Length of the Base BC (which is also the diameter of the semi circle) = 4 units and consequently the radius = 2 units
Length of the altitude AH = 5 units, hence:
a) the Area of ABC = (Base x Altitude)/2 = (4 x 5)/2 = 10 units²
b) the area of the semi circle is: (π x R²)/2 = (π x 2²)/2 = 6.28 units²
Total area = 16.28 units²
