Question 403622
the sum of two numbers is 50. one number is 1 less than 2 times the other number.

Sol'n:
let: x - the first number
     y - the second number
x + y = 50 ---(1)
x = 2y - 1 ---(2)

(1)-(2)
  x + y = 50
-(x - 2y) = -1
----------------

3y = 51
y = 17 

for x:
x = 2(17)-1
x = 33

thus:
x = 33
y = 17 ----answers
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