Question

1. Cost of 7 pens and 8 pencils is 87 and cost of 6 pens and 4 pencils is
66. Write linear equations representing the above data and draw its graph.​

Answer 1

• let cost of 1 pen be x
• let cost of 1 pencil be y
• then ,
• 7x + 8y = 87
• 6x + 4y = 66

Answer 2

Step-by-step explanation:

7y+8x=87 (1)

6y + 4x=66 (2)

multiplying equation 2nd and subtracting equation

12y+8x-7y-8x=132-87

5y=45

y=45/5

=9

now putting y =9

7(9) +8x=87

63+8x=87

8x=87-63

8x=24

x=24/8

=3

Hence ,the cost of 1 pen =Rs 9.cost of pencil is rs 3