Question

Consider a square of length $3$ units and two points on each side of the square, trisecting it into equal parts. The area of the octagon made by these eight points will be

• A. $4$ sq. units
• B. $6$ sq. units
• C. $7$ sq. units
• D. $8$ sq. units

Answer 1

The correct option is C $7$ sq. units

Area of octagon $ABHGDEFE=$ Area of rectangle $ABDC+$ Area of trapezium $BHGD+$ Area of trapezium $ACFE$.
$=(1\times 3)+\frac{1}{2}\times (1+3)\times 1+\frac{1}{2}\times (1+3)\times 1$
$=7$sq unit.