Answer:
4,200. I'm pretty sure that's the correct answer. I apologize if it's incorrect.
Step-by-step explanation:
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!
Answer:
Step-by-step explanation:
Given: The total number of ways of to choose 3 contestants out of 7 (including me and my friend)=35..................> Total outcomes.
Favorable outcomes = 2
Then the probability that me and my friend are both chosen =
Thus , the probability that me and my friend are both chosen =
Step-by-step explanation:
the answer would be -9.
28x -63 = -315
add 63 to -63 and -315
there u get this
28x= -252
then divide 28 both sides
x=-9