Answer:
10 cm²
Step-by-step explanation:
The area of a square = s², where s is the measure of the side
To calculate the side use Pythagoras' identity
Consider the lower side with right triangle legs 3 and 1, then
side² = 3² + 1² = 9 + 1 = 10 ( take the square root of both sides )
side = , thus
area = ( )² = 10 cm²