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Math Help - pre-calc numbers problem-urgent help!

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    pre-calc numbers problem-urgent help!

    The sum of two numbers is twice their difference. The larger number is 7 more than twice the smaller. Find the numbers.
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    Quote Originally Posted by tmac11522 View Post
    The sum of two numbers is twice their difference. The larger number is 7 more than twice the smaller. Find the numbers.
    Let the numbers be a and b

    a+b = 2(a-b) (eq1)

    b-2a = 7 (eq2)


    From this you can solve it simultaneously
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  3. #3
    Junior Member rubix's Avatar
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    Quote Originally Posted by tmac11522 View Post
    The sum of two numbers is twice their difference. The larger number is 7 more than twice the smaller. Find the numbers.
    let x and y be two required numbers. Let x be the larger number in concern.

    1) the sum of two numbers is twice their difference

     x+y = 2 (x-y)

    2) the larger number is 7 more than twice the smaller.

    x = 2y + 7

    you now have two equations and two unknown. Use substitution to solve.


    P.S. this is wrong section. If this is a pre-calc problem you should have posted it in pre-calc section.
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