Question 95511
Factor the following trinomials. 
16x^2 + 40xy + 25y^2 
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The square root of the 1st term is 4x
The square root of the 3rd term is 5y
The 2nd term is 2*4x*5y
So, the trinomial is a perfect trinomial square.
It factors as follows:
(4x+5y)^2
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Cheers,
Stan H.