Question 1121501
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<pre>
2*|AM| = |AB|     (the lengths)


2*(2x^2+16) = 6x^2


4x^2 + 32 = 6x^2


32 = 2x^2


x^2 = 32/2 = 16


x = {{{sqrt(16)}}} = 4.


|AB| = {{{6*4^2}}} = 6*16 = 96.
</pre>

Solved.