Question

Find the solution of the system of equations. minus, 4, x, minus, y, equals, 6 −4x−y= 6 8, x, minus, 9, y, equals, 10 8x−9y= 10 Answer Attempt 1 out of 2 left bracket( , right bracket) Submit Answer

Answer 1

Answer:

  (x, y) = (11/7, 2/7)

Step-by-step explanation:

You want the solution to the system of equations ...

• 4x -y = 6
• 8x -9y = 10

Elimination

We notice the x-coefficients have the ratio 1:2. This means we can eliminate the x-variable by subtracting the second equation from 2 times the first:

  2(4x -y) -(8x -9y) = 2(6) -(10)

  8x -2y -8x +9y = 12 -10 . . . . . . . eliminate parentheses

  7y = 2 . . . . . . . . . . . . . . . . collect terms

  y = 2/7 . . . . . . . . . . . . divide by 7

Substituting into the first equation gives ...

  4x -2/7 = 6

  4x = 6 2/7 = 44/7 . . . . . add 2/7

  x = 11/7 . . . . . . . . . . . divide by 4

The solution is (x, y) = (11/7, 2/7).