What is the solution to this system of equations? x + 2y = 9 3x - 2y = 3 A.(3, 3) B.(3,5) C. (4, 12) D. (9,7)

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  A.  (3, 3)

Step-by-step explanation:

The coefficients of y are opposites, so adding the two equations will eliminate y.

  (x +2y) +(3x -2y) = (9) +(3)

  4x = 12 . . . simplify

  x = 3 . . . . . divide by 4

Using the first equation, we can find y:

  3 +2y = 9 . . . . . .substitute for x

  2y = 6 . . . . . . . .  subtract 3

  y = 3 . . . . . . . . . . divide by 2

The solution is (x, y) = (3, 3).

Additional comment

For this problem, it is easy to just try the answers. You don't have to go far to show the first answer (A) satisfies both equations.

  3 + 2(3) = 9; 3(3) -2(3) = 3

Mode = number which appears the most

The mode for your question is 5