Question

Romila went to a stationery shop and purchased 2 pencils and 3 erasers for Rs 9. Her friend Sonali saw the new variety of pencils and erasers with Romila, and she also bought 4 pencils and 6 erasers of the same kind for Rs18. Represent this situation algebrically and graphically.

Answer 1

Let the cost of one pencil = Rs. x
Let the cost of one eraser = Rs. y

Romila purchases 2 pencils and 3 erasers for Rs. 9

Cost of 2 pencils = 2x
Cost of 3 erasers = 3y
Total Cost = Rs. 9

So, we have:

2x + 3y = 9

Sonali purchases 4 pencils and 6 erasers for Rs 18.

Cost of 4 pencils = 4x
Cost of 6 erasers = 6y

Total Cost = 18

So, we have:

4x + 6y = 18
So, 2(2x + 3y) = 18

4x+6y=18

The two lines are coincident.