Question

$x$ articles are bought at $Rs(x-4)$. If the total cost of all these articles is $Rs45.$ How many articles were bought ?

Answer 1

Solution:

$x$ articles bought at Rs$(x-4)=x(x-4)=x^2-4x$

we can form equation

$x^2-4x=45$

$x^2-4x-45=0$

$(x-9)(x+5)=0$

$\therefore x=9$

Since number of articles can't be negative.

There are $9$ articles are bought