Question

the area of a square is 100 cm². what is the perimeter? 10 cm 50 cm 40 cm 25 cm

Explanation:

Step1: Find side - length of square

Let the side - length of the square be $s$. The area formula of a square is $A = s^{2}$. Given $A = 100\ cm^{2}$, then $s=\sqrt{A}=\sqrt{100}=10\ cm$.

Step2: Calculate perimeter of square

The perimeter formula of a square is $P = 4s$. Substitute $s = 10\ cm$ into the formula, we get $P=4\times10 = 40\ cm$.

Answer:

40 cm