Question

Question no 14 ,12 ,10

Answer 1

Let breadth of rectangle = x
Length of rectangle = x+9
Area of rectangle= l×b
=(x+9)x=x² + 9x

Now, increase the both length and breadth
New length =( x+9)+3=x+12
New breadth = x+3
Area of new rectangle=(x+12)(x+3)

=x² + 3x +12x+36=x²+15x+36

Now, according to question
(x²+9x)+84=x²+15x+36
x²+9x+84-(x²+15x+36)=0
x²+9x +84-x²-15x-36=0
-6x+48=0
x-8=0
x=8

x=8
x+9=17
Length & breadth of given rectangle is 17 & 8 respectively.