If each of the 4 sloping side ahs length 10 cm
This implies they have length 40 cm altogether
To find the base length, simply subract the 40 cm from the total length of 68cm
68 - 40 = 28
each base length = 28/4 = 7cm
Area of the square base is = l x l = 7 x 7 = 49 cm²
