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Word problem solving - one degree one variable equation
Question:
There are three consecutive even integers. The largest subtract the least divide by the middle is equal to one. Find the three numbers.
Solution:
the first even integer is: x
the second consecutive even integer is: (x + 2)
the third consecutive even integer is: (x + 4)
given: the largest subtract the least divide by the middle is equal to one.
so we get the equation: [(x + 4) - x]/(x + 2) = 1
both side of the equation multiply (x + 2)
(x + 4) - x = 1(x + 2)
remove parenthesis
x + 4 - x = x + 2
x + 2 = 4
x = 2
x + 2 = 2 + 2 = 4
x + 4 = 2 + 4 = 6
so the three consecutive even integer are: 2, 4, and 6.

The three consecutive even integers are x, (x + 2), and (x + 4). Their relationship is that the largest subtract the least divide by the middle is equal to one. so we get the equation [(x + 4) - x]/(x + 2) = 1. To remove the denominator, both sides of the equation multiply the denominator. Simplift the equation by moving all variables into the left side of the equation and moving all numbers into the right side of the equation. (note: when move an item cross the equal sign, the item will change sign, which equivalent to add the same item on both side of the equation.) Make the first degree one variable equation to the standard form ax = b, then x = b/a. When find the value of x, we ge the value of (x + 2) and the value of (x + 4). The value of x, (x + 2), (x + 4) are three consecutive even integers.