the area of rectangle get reduced by 8m2 when its length is reduced by 5m and breadth increase by 3m if we increase the length by 3m and breadth by 2m the area is increased bt 74m2.find the length breadth of rectangle by linear equation
plzz i need it
Answers
Answered by
2
Answer:
Step-by-step explanation:
given
let area be a
length be l
breadth be b
a-8=(l-5)(b+3)
a=(lb+3l-5b-15+8)
=lb+3l-5b-7--(1)
a+74=(l+3)(b+2)
a=lb+2l+3b+6-74
=lb+2l+3b-68---(2)
(1)=(2)
lb+3l-5b-7=lb+2l+3b-68
l-8b+61=0
l+61=8b--(3)
b=l+61/8
and length=8b-61
As there are two equations and three unknowns we cant solve the equations
Answered by
2
Answer:
HOPE THIS HELP YOU
Step-by-step explanation:
Let the length and the breadth of the rectangle be x m and y m, respectively.
∴ Area of the rectangle = (xy) sq.m
Case 1: When the length is reduced by 5m and the breadth is increased by 3 m:
New length = (x – 5) m
New breadth = (y + 3) m
∴ New area = (x – 5) (y + 3) sq.m
∴ xy – (x – 5) (y + 3) = 8
⇒ xy – [xy – 5y + 3x – 15] = 8
⇒ xy – xy + 5y – 3x + 15 = 8
⇒ 3x – 5y = 7 ………(i)
Case 2: When the length is increased by 3 m and the breadth is increased by 2 m:
New length = (x + 3) m
New breadth = (y + 2) m
∴ New area = (x + 3) (y + 2) sq.m
⇒ (x + 3) (y + 2) – xy = 74
⇒ [xy + 3y + 2x + 6] – xy = 74
⇒ 2x + 3y = 68 ………(ii)
On multiplying (i) by 3 and (ii) by 5, we get:
9x – 15y = 21 ……….(iii)
10x + 15y = 340 ………(iv)
On adding (iii) and (iv), we get:
19x = 361 ⇒ x = 19
On substituting x = 19 in (iii), we get:
9 × 19 – 15y = 21
⇒171 – 15y = 21
⇒15y = (171 – 21) = 150
⇒y = 10
Hence, the length is 19m and the breadth is 10m.
Similar questions
Math,
5 months ago
History,
5 months ago
English,
10 months ago
Social Sciences,
10 months ago
Physics,
1 year ago