Question

the price of 3note book and 5 pen together is 75 rupees.The price of 3 note book and 10 pens together is 90 rupees.what is the price of a not book ? what is the price of a pen​

Answer 1

Answer:

let the price of note book = x

let the price of pen = y

A/Q in 1 equ.

3x+5y=75

A/Q in 2.equ.

3x +10y =90

in 1 & 2 equ.

3x +5y = 75

3x +10y= 90

_ _ _

0-5y =15

5y=-15

y = -15/5

y=-3

& now put the y value in 1 equ.

3x+5y=75

3x+5*-3=75

3x-15=75

3x=75+15

3x=90

x=90/3

x=38

so price of notebook =30

& price of pen =-3

i hope it will works