Surface Area (SA) = Base Area (Ab) + Lateral Area (AL)
Base Area = 36cm^2
Lateral Face Area = 48cm^2
*If this is a quadrilateral pyramid, then it has 4 lateral faces, so just multiply the "one" lateral face by 4.
Lateral Area (AL) = 4 x Lateral Face Area
-> AL = 4 x 48 = 192 cm^2
So:
SA = Ab + AL
-> SA = 36 + 192
-> Surface Area = 228 cm^2