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    help me plz does ny 1 no aw 2 do simolainous equations? da first q looks like dis: 3p+4q=29
    5p-2q=5
    WILL SUM ONE PLZ HELP ME I'M GOIN INSANE WID ALL DEEZ Q!!!
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    (Original post by hotchick200)
    help me plz does ny 1 no aw 2 do simolainous equations? da first q looks like dis: 3p+4q=29
    5p-2q=5
    WILL SUM ONE PLZ HELP ME I'M GOIN INSANE WID ALL DEEZ Q!!!
    Well, you have to cancel one of the letters from one of the equations. Do this by multiplying one, the other or both by a number.
    3p+4q=29 (call this 1)
    5p-2q=5 (call this 2)
    If we multiply equation 2 by 2, we get:
    10p-4q=10
    Now you have:
    3p+4q=29
    10p-4q=10
    As the signs are different, add the two equations together (put all the stuff on the left side together and all the stuff of on the right side together). If the signs were the same, you would subtract one equation from the other (it doesn't matter which way round, chose the one with the easiest subtractions).
    If we add together, we get:
    3p+10p+4q-4q=10+29
    Therefore:13p=39
    So p=3
    Substitute into 1:
    3x3+4q=29
    9+4q=29
    4q=20
    q=5
    Then check with number 2 (god practice to do this if you're not happy with them)
    5x3-2x5=15-10=5 (which is correct)
    If you follow this process for each one, it's easy enough.
    And just to show you they're not that long, this is all of it without the words:
    3p+4q=29 (1)
    5p-2q=5 (2) x2
    10p-4q=10 (2a)
    13p=39 (1+2a)
    p=3
    In 1: 9+4q=29
    q=5
    Check in 2:5x3-2x5=15-10=5
 
 
 
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