Question

16. The length of a rectangle exceeds its breadth by 7 cm. If the length is decreased by 4 com
and the breadth is increased by 3 cm, the area of the new rectangle is the same as the area
of the original rectangle. Find the length and breadth of the original rectangle
17. The base of a triangle is th the length of the corresponding altitude. If the altitude is
Increased by 3 cm and the base is decreased by 2 cm, the area of the triangle remains the same
Find the base and altitude of the triangle
16. A boat covers a certain distance downstream in 2 hours. It covers the same distance upstream
in 2 hours. The speed of the boat in still water is 18 km/h. Find the speed of the water,
Also find the distance covered by the boat.​

Answer 1

Step-by-step explanation:

16). Let breadth is b

then length = b+7

area of rectangle = L×B

= (B+7)×B

=B2 +7B

new breadth= b+3

new length=b+7-4=b+3

area =L×B

=(b+3)×(b+3)

=(b+3)2

(=a+b)2= a2+2ab+b2)....1

now put the value of a =b and value of b = 3 in equation 1

=b2+6b+9

acc.. to question

original rectangle = new rectangle

b2+7b = b2+ 6b+9

b2 +7b-b2-6b=9

b = 9

hence breadth = 9

now putt the value of b in ( b + 7)

= 9+7

=16

L =16