SOLUTION: What is the value of n so that the expression x² + 12x + n is a perfect square trinomial? Multiple choice: 6 36 72 144

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: What is the value of n so that the expression x² + 12x + n is a perfect square trinomial? Multiple choice: 6 36 72 144       Log On


   

Question 729064: What is the value of n so that the expression x² + 12x + n is a perfect square trinomial?
Multiple choice:
6
36
72
144

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+%2B+12x+%2B+n+
+%28+x+%2B+sqrt%28n%29+%29%5E2+
+x%5E2+%2B+2%2Asqrt%28n%29%2Ax+%2B+n+=+x%5E2+%2B+12x+%2B+n+
+2%2Asqrt%28n%29+=+12+
+sqrt%28n%29+=+6+
+n+=+36+
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check:
++%28+x+%2B+sqrt%28n%29+%29%5E2++=+%28+x+%2B+6+%29%5E2+
+%28+x+%2B+6+%29%5E2+=+x%5E2+%2B+12x+%2B+36+
OK