Your answer is D. 16x² - 56xy + 49y².
A perfect square trinomial is the result of a squared binomial, like (a + b)². Using this example, the perfect square trinomial would be a² + 2ab + b², as that is what you get when you expand the brackets.
Therefore, to determine which of these is a perfect square trinomial, we have to see if it can be factorised into the form (a + b)².
I did this by first square rooting the 16x² and 49y² to get 4x and 7y as our two terms in the brackets. We automatically know the answer isn't A or B as you cannot have a negative square number.
Now that we know the brackets are (4x + 7y)², we can expand to find out what the middle term is, so:
(4x + 7y)(4x + 7y)
= 16x² + (7y × 4x) + (7y × 4x) + 49y²
= 16x² + 28xy + 28xy + 49y²
= 16x² + 56xy + 49y².
So we know that the middle number is 56xy. Now we assumed that it was (4x + 7y)², but the same 16x² and 49y² can also be formed by (4x - 7y)², and expanding this bracket turns the +56xy into -56xy, forming option D, 16x² - 56xy + 49y².
I hope this helps!
Sin x = cos (90-x)
90-x = 19
x = 71
The answer is 71 degrees.
Answer:
b
Step-by-step explanation:
the sum of 3 and 7 is 3+7. then times x
Answer:
Step-by-step explanation:
we know that
The surface area of a rectangular prism is equal to the area of its six rectangular faces
using the net
The surface area is equal to
![SA=2[(16)(6)]+2[(16)(8)]+2[(8)(6)]](https://tex.z-dn.net/?f=SA%3D2%5B%2816%29%286%29%5D%2B2%5B%2816%29%288%29%5D%2B2%5B%288%29%286%29%5D)
The product would be negative. Since there are three negative integers, the product would be negative. Two negatives make a positive, but another negative makes the end result negative.
