<p>whats an easy way to solve these two problems?</p>
<p>1.what is the least positive integer k for which 168k is the square of an integer?</p>
<li>The function f is defined by f(n) = n^2/9 + 12, if f(3a) = 7a, what is one possible value of a? </li>
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<p>Thanks</p>
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<li>168k = 2 * 2 * 2 * 3 * 7 * k</li>
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<p>So, to make it square of an integer, you will need a 2, a 3, and a 7, making k a 42. Am I right? Not sure LOL</p>
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<li>There are answer choices, right? So substitute the choices rather than solving. It is the best method for this kind of questions. </li>
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<p>Well, if you really want to solve it, here it is.</p>
<p>f(3a) = (3a)^2 / 9 + 12 = 7a =>> a^2 - 7a + 12=0 =>>> a = 3 a = 4</p>
<p>See which one is among the answer choices.</p>
<p>yup yup those are the answers...</p>
<p>so for #1 you just did prime factorization
and #2 was a stupid question gah...damn brain farts. </p>
<p>thanks btw</p>
<p>you were looking for an easy way, but I doubt if I provided you that. anyways, you are welcome!</p>