Dear student,
In the given figure we can see that 2 triangles PSR and PQR have been formed.
Area of a trinagle = 1/2 * Base * side
Area of triangle PSR = 1/2 * 12 * 4 = 24 cm2
Area of triangle PQR = 1/2 * 12 * 8 = 48 cm2
Total area = 24+48 = 72 cm2
Regards
