Length : breadth =3:2 length is increased by 5m keeping the breadth same New area become 2600m2 Formula used: Area of rectangle = Length × breadth Perimeter =2 (Length + breadth ) Calculation: Let length & breadth be '3y' & '2y' respectively. According to the question ⇒2600=(3y+5)×2y ⇒2600=6y2+10y ⇒6y2+10y−2600=0 ⇒3y2+5y−1300=0 ⇒3y2−60y+65y−1300=0 ⇒3y(y−20)+65(y−20)=0 ⇒(3y+65)(y−20)=0 Since, length can not be negative.
⇒y=20 Therefore, length & breadth of original rectangle 3y=3×20=60 2y=2×20=40 Hence, perimeter =2(60+40)=200 ∴ Perimeter of the rectangle is 200m .