Question

Which ordered pair (r, s) is the solution to the given system of equations?

5r+75 - 61
-5r+75=-19

Answer 1

(8,3)

Explanation:

Answer 2

Option 4 - (8,3)

Explanation:

Given : The system of equations,

`5r+7s=61` ......(1)

and
`-5r+7s=-19`......(2)

To find : Which ordered pair (r, s) is the solution to the given system of equations?

Solution :

To get the solution we solve both the equations,

Add equation (1) and (2),

`5r+7s+(-5r+7s)=61+(-19)`

`5r+7s-5r+7s=61-19`

`14s=42`

`s=(42)/(14)`

`s=3`

Substitute the value of s in equation (1),

`5r+7(3)=61`

`5r+21=61`

`5r=61-21`

`5r=40`

`r=8`

The value of r=8 and s=3.

So, ordered pair (8,3) is the solution to the given system of equations.

Therefore, option 4 is correct.