40th B.P.S.C. (Pre) 1995
The perimeter of a square is (4a+8) unit, the area of square is-
a$(a^2 + 4a + 4)$ unit²✓ Correct
b$(b - a - 8)$ unit²
c$(a + 2 + 4)$ unit²
d$(4a^2 + a - 4)$ unit²
Explanation
Perimeter of square = $4a + 8$ Side of square = $\frac{4a + 8}{4} = (a + 2)$ Unit here, side of a quare = $\frac{Perimeter}{4}$ Area of square, (side)² = $(a + 2)^2$ Unit² = $(a^2 + 4a + 4)$ Unit²
general-science