Question

23. Siri bought 2 notebooks and 3 pens for Rs 90. Lakshmi bought
4 notebooks and 5 pens for Rs 140. Form linear equations for the given
situation to find the cost of a pen and a notebook
​

Answer 1

Step-by-step explanation:

let notebook be X

and pen by Y

then, according to question

2x + 3y = 90 ------------1

4x + 5y= 140-------------2

from eq 1

x= 90 - 3y/2

put x in eq 2

4(90 - 3y/2) + 5y = 140

360-12y +10y=140

-2y=-80

y=40

put y in eq 1

2x +3(40)=90

2x + 120=90

2x= 90-120

x= -15