Let's classify the triangle into big , medium and small. The question said big triangle total area is 323cm^2 , and unshaded small triangle EGF area = 11cm^2 , if you subtract EGF from big triangle , you get 312cm^2 , then given also medium triangle with 14cm high , 16cm wide , so one medium triangle area is 112cm^2 , now use creative method to divide the 312cm^2 big triangle into A , B , C medium trapezium , each with 104cm^2 area , then 112 - 104 = 8cm^2 u get answer for small shaded triangle area , ok??
**in my working I wrote unit cm^3 which is wrong , should be cm^2