Question

The total cost of 6 books and 7 pens is 79 and total cost of 7 books and 5 pens is 77. find cost of 1 book and 1 pen.​

Answer 1

Answer:

12

Step-by-step explanation:

Let the cost of the book be x

And the cost of pen be y

Then the cost of 6 books n 7 pens is

6x+7y = 79

And 7x+6y = 77

Now let us add both equations,

13x + 13y = 156

X+y = 12

Let us subtract both equations,

-x + y = 2

Now let us add the equations so obtained then,

X-x + y +y = 12 + 2

2y = 14

y = 7

Substitute in one equation then,

X + 7 = 12

X = 5

So the cost of one book is 5

And one pen is 7

So the cost of 1 book and 2 pens is

X + y = 5 + 7 = 12.

GOD BLESS THE PRINCESS.

Answer 2

Step-by-step explanation:

Hope this helps u..............,