Question

8. A
is
ar
2. Find the length of the rectangle if the perimeter
and width are:
(a) Perimeter = 86 cm, width = 18 cm
(b) Perimeter = 128 cm, width = 25 cm
(c) Perimeter = 151 cm, width = 29.5 cm

​

Answer 1

Answer:

required lengths are

(a) 25 cm

(b) 39 cm

(c) 46 cm

Step-by-step explanation:

if length oh a rectangle is a cm

width of the rectangle be b cm

then perimeter of the rectangle is p = 2(a + b) cm

(a) perimeter p = 86 cm

width b = 18 cm

then 86 = 2 (a+18) [according as above formula]

⇒ a + 18 = 43

⇒ a = 25 cm

hence length of this rectangle is 25 cm

(b) perimeter p = 128 cm

width b = 25 cm

then 128 = 2(a+25)  [according as above formula]

⇒ a+25 = 64

⇒ a = 39 cm

hence length of this rectangle is 39 cm

(c) perimeter p = 151 cm

width b = 29.5 cm

then 151 = 2(a+29.5)  [according as above formula]

⇒ a + 29.5 = 75.5

⇒ a = 46 cm

hence width of this rectangle is 46 cm