9514 1404 393
Answer:
(4x +5)
Step-by-step explanation:
The square of a binomial is ...
(a +b)² = a² +2ab +b²
We assume that the given trinomial is a perfect square, so we can find the terms of the squared binomial by looking at the square roots of the first and last terms:
√(16x²) = 4x
√25 = 5
So, our first choice of side length for the square is ...
s = (4x +5) . . . . . side length of the square
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Using the above identity, we can verify that the square of this gives the right area:
A = s² = (4x +5)² = (4x)² +2(4x)(5) +5²
A = 16x² +40x +25 . . . . . . as required
