we know that
surface area=area of the base+4*[area of one lateral triangle side]
area of the base=b²
b is the side length of the square
b=14 cm
area of the base=14²-----> 196 cm²
area of one lateral triangle side=b*h/2
b is the side length of the square
b=14 cm
h is the height of the lateral triangle side
h is equal to the slant height
h=15 cm
area of one lateral triangle side=14*15/2----> 105 cm²
surface area=196+4*[105]------> 616 cm²
the answer is
the surface area is 616 cm²
