Ask Question
22 October, 15:22

If 3x+2y=12 and - 4x+6y=24 what is the value of - x+2y

+5
Answers (1)
  1. 22 October, 16:15
    0
    (1) 3x+2y=12

    (2) - 4x+6y=24

    Solving the system of equations using the method of substitution:

    Isolating y in the first equation:

    (1) 3x+2y=12→3x+2y-3x=12-3x→2y=12-3x→2y/2 = (12-3x) / 2→y = (12-3x) / 2

    Replacing "y" by (12-3x) / 2 in the second equation:

    (2) - 4x+6y=24

    y = (12-3x) / 2→-4x+6[ (12-3x) / 2]=24

    Solving for x:

    -4x+3 (12-3x) = 24

    -4x+36-9x=24

    -13x+36=24

    -13x+36-36=24-36

    -13x=-12

    -13x / (-13) = - 12 / (-13)

    x=12/13

    Replacing "x" by 12/13 in y = (12-3x) / 2

    x=12/13→y=[12-3 (12/13) ]/2

    y = (12-36/13) / 2

    y={[ (13) (12) - 36]/13}/2

    y=[ (156-36) / 13]/2

    y = (120/13) / 2

    y = (120/13) (1/2)

    y=60/13

    x=12/13; y=60/13

    -x+2y=-12/13+2 (60/13)

    -x+2y=-12/13+120/13

    -x+2y = (-12+120) / 13

    -x+2y=108/13

    Answer: The value of - x+2y is 108/13
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “If 3x+2y=12 and - 4x+6y=24 what is the value of - x+2y ...” in 📘 Mathematics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers