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Question 650573: how would you write an equation for this problem and solve it:
the sum of three numbers is 5. the first number minus the second plus the third is 1. the first minus the third is 3 more than the second. find the numbers
Found 2 solutions by stanbon, MathTherapy:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! the sum of three numbers is 5. the first number minus the second plus the third is 1. the first minus the third is 3 more than the second. find the numbers
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Equation:
x + y + z = 5
x - y + z = 1
x - z = y +3
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x + y + z = 5
x - y + z = 1
x - y - z = 3
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Use any method to solve the system to get:
x = 5
y = 2
z = -1
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Cheers,
Stan H.
Answer by MathTherapy(10552)  (Show Source):
You can put this solution on YOUR website!
how would you write an equation for this problem and solve it:
the sum of three numbers is 5. the first number minus the second plus the third is 1. the first minus the third is 3 more than the second. find the numbers
Let 1st, 2nd, and 3rd numbers be F, S, and T, respectively
Then:
F + S + T = 5 ----- eq (i)
F S + T = 1 ------ eq (ii)
F T = S + 3 ----- F S T = 3 ----- eq (iii)
2F + 2T = 6 ------ Adding (ii) & (i) ----- F + T = 3 ----- eq (iv)
2T = - 2 ------ Subtracting (iii) from (ii)
T, or 3rd number =  , or 
F 1 = 3 ----- Substituting 1 for T in eq (iv)
F, or 1st number = 3 + 1, or 
4 + S 1 = 5 ------- Substituting 4 for F, and 1 for T in eq (i)
S + 3 = 5
S, or 2nd number = 5 - 3, or 
Send comments and thank-yous to D at MathMadEzy@aol.com
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