Question

Which ordered pair is a solution of this

equation?
-6x - 7y = 4
Click on the correct answer.
(2,-2)
(-2,2)
(-3,2)
(2,-3)

Answer 1

(-3, 2)

Explanation:

Substitute each ordered pair into the equation.

(2, - 2)

`- 6(2) - 7( -2) = 4`

`- 12 + 14 = 4`

This ordered pair is not a solution because - 12 + 14 = 2

(-2, 2)

`- 6( - 2) - 7(2) = 4`

`12 - 14 = 4`

This ordered pair is not a solution because 12 - 14 = - 2. Also, because this ordered pair is just the inverse of the previous one you have calculated, you can tell it will not give a result of 4.

(-3, 2)

`- 6( - 3) - 7(2) = 4`

`18 - 14 = 4`

This ordered pair is a solution because 18 - 14 = 4.

(2, - 3)

`- 6(2) - 7( - 3 ) = 4`

`- 12 + 21 = 4`

This ordered pair is not a solution because - 12 + 21 = 9.

Answer 2

(- 3, 2 )

Explanation:

To determine which ordered pair is a solution, substitute the x and y- coordinates of the given points into the left side of the equation.

If the result is equal to the right side then the pair is a solution.

(2, - 2)

- 6(2) - 7(- 2) = - 12 + 14 = 2 ≠ 4 ← not a solution

(- 2, 2 )

- 6(- 2) - 7(2) = 12 - 14 = - 2 ≠ 4 ← not a solution

(- 3, 2 )

- 6(- 3) - 7(2) = 18 - 14 = 4 = right side ← a solution

(2, - 3 )

- 6(2) - 7(- 3) = - 12 + 21 = 9 ≠ 4 ← not a solution

(- 3,2 ) is a solution of the equation