The answer is letter choice B
recall in a perfect square trinomial, the middle term is the tale-tell guy, we know the middle term is the product of 2 and the two other guys without the exponent, so in this case 6x = 2*√x² * √c.

Answer: B
Explanation: an isosceles triangle has 2 sides that are the same, so if the base angles are both 34° then you can multiply that by 2 to get 68°. After that you know that you're still missing one of the angles so that missing angle is x. The equation you can set up to solve for x is the following: 68° + x° = 180°
Hope this helped! :)
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