three consecutive even integers are such that the square of the thrid is 76 more than the square of the second. find the three integers.
Let the first even integer be : x Other will be : (x + 2) And third will be: (x + 4) \[(x+4)^2 = 76 + (x+2)^2\] \[(x+4)^2 - ( x+2 )^2 = 76\] Solve for x now..
You can use the formula: \[(a+b)^2 = a^2 + b^2 + 2ab\]
or we can call the middle one \(x\) since the first one does not enter in to the question solve \[x^2+76=(x+2)^2\] \[x^2+76=x^2+4x+4\] \[4x+4=76\] \[4x=72\] \[x=18\] so the three are \(\{16,18,20\}\) and the smallest one is 16
Is this a factoring method
no factoring needed for this problem
\[x^2+76=(x+2)^2\] looks like it might be a quadratic equation, but it is not one because there is an \(x^2\) on both sides, subtract it from both sides and you have a linear equation
No factoring method, x squared terms will automatically cancel each other you have to solve for x and constant terms...
just learning the quadratic formula trying to understand each method not to be confused. Thank you
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