First, we will find half of the diagonal of the square using the Pythagorean Theorem.
Let $d$ be half the diagonal of the square.
$2^2 + d^2 = 10^2$
$4+d^2 = 100$
$2d = 2\sqrt{96}$ = 18.547236991
Using the formulas:
$A=a^2$
$d=2a$
Assuming if A = area, the area of the base square would be:
$A=\frac12 d^2$
$A=\frac12 \times 18.55^2$ (diagonal)
$A≈172$
The side length of the base will be $\sqrt{172} ≈ 13.11$
Finally, we will find the Lateral Surface Area, L, using the formula:
L= $a \sqrt {a^2+4h^2}$
L= $13.11\times\sqrt{13.11^2+4\times2^2}≈179.69411$
The lateral surface area of the square based pyramid is $≈179.7$