Question 110012
Begin by letting x equal one of the positive even integers. Then the next consecutive
positive even integer is x + 2 (because even numbers are 2 units away from the preceding
even integer.)
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Square the two integers to get {{{x^2}}} and {{{(x+2)^2 = x^2 + 4x + 4}}}. Then add these
two squares and get:
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{{{x^2 + x^2 + 4x + 4}}}
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You can combine the two {{{x^2}}} terms to simplify this to:
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{{{2x^2 + 4x + 4}}} 
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and you are told that this sum equals 340. In equation form this is:
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{{{2x^2 + 4x + 4 = 340}}}
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You can simplify this a little by dividing both sides (each term) by 2 because 2 is a factor
of all the terms in this equation. Dividing by 2 results in:
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{{{x^2 + 2x + 2 = 170}}}
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Get this into standard quadratic form by subtracting 170 from both sides of the equation so
that the right side is zero. This subtraction leads to:
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{{{x^2 + 2x - 168 = 0}}}
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The left side of this equation can be factored. This factoring leads to:
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{{{(x + 14)*(x - 12) = 0}}}
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This equation will be true if either of the factors is zero, because a multiplication
by zero on the left side results in the entire left side becoming zero and therefore
equal to the right side.  So find out what values of x cause a factor to equal zero by
setting each factor equal to zero:
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{{{ x + 14 = 0}}}
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Solve by subtracting 14 from both sides to get:
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{{{x = -14}}}
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So one of the integers that could satisfy this equation is -14, but we can eliminate
this because the problem requires that the consecutive even integers be positive. 
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Setting the other factor equal to zero:
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{{{x - 12 = 0}}}
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Solve for x by adding 12 to both sides to get:
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{{{x = 12}}}
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This answer tells us that the first positive even integer is 12, and therefore, then next
consecutive even integer is 14.
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Check these answers. Does {{{12^2 + 14^2 = 340}}}? Yes it does because {{{12^2 = 144}}} and {{{14^2 = 196}}}. 
So our check is {{{144 + 196 = 340}}} and this means that our answer works. 
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The answer to this problem is that two consecutive positive even integers that work are 12 and 14
because when their squares are summed, the total is 340.
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Hope this helps you to understand the problem.
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