Question

5 pencils and 7 Pens together cost Rupees 50 where as for 7 pencils and 5 pens together cost rupees 46 find the cost of one pencil and that of 1 pen.
Pls give the answer in a book and giv the pic with all steps.

Answer 1

$put \: that \: pencil = x \\ and \: pens = y \\ then \: \: \: \: \: \: 5x + 7y = 50 - - - eqn \: 1 \\ 7x + 5y = 46 - - - eqn \: 2 \\ if \: eqn \: 1 \times 7 and eqn2 \times 5 \\ then \: \\ 35x + 49y = 350 - - - eqn3 \\ 35x + 25y = 230 - - - eqn4 \\ eqn3 - eqn4 \\ 24y = 120 \\ y = 30 \\ put \: up \: the \: value \: of \: eqn1 \\ \\ 5x + 7 \times 30 = 50 \\ 5x = 50 - 210 \\ x = - 160 \div 5 \\ x = - 32$
there value of x is negative.
and prise is not negative available.
so, cheak the question plzz.