Answer:
Remember that a perfect square trinomial can be factored into the form (a+b)^2
or (a-b)^2
Examples:
(x+2)(x+2) is a perfect sq trinomial --> x^2+4x+4
(x-3)(x-3) is a perfect sq trinomial --> x^2-6x+9
(x+2)(x-3) is not a perfect square trinomial because its not in the form (a+b)^2 or (a-b)^2
Now to answer your question,
for the first one, x^2-16x-64, you cannot factor it so it is not a perfect square trinomial
for the second one, 4x^2 + 12x + 9, you can factor that into (2x+3)(2x+3) = (2x+3)^2 so this is a perfect square trinomial
for the third one, x^2+20x+100 can be factored into (x+10)(x+10) so this is also a perfect square trinomial
for the fourth one, x^2+4x+16 cannot be factored so this is not a perfect square trinomial
Therefore, your answer is choices 2 and 3
Read more on Brainly.com - brainly.com/question/10522355#readmore
Step-by-step explanation:
B Is the answer ......... z
Answer:
15.75
Step-by-step explanation:
So we know 5% is 1/20 out of 100 (20x5=100) so then we need to set up the equation to find how much 5% of 15 is. Which is .75 cents. So we then add the 75 cents to the already $15 shipping fee to get an answer of 15 dollars and seventy five cents.
<h3>
Answer: Choice B</h3><h3>
y = x^2 + 7x + 1</h3>
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Proof:
A quick way to confirm that choice B is the only answer is to eliminate the other non-answers.
If you plugged x = 1 into the equation for choice A, you would get
y = -x^2 + 7x + 1
y = -1^2 + 7(1) + 1
y = -1 + 7 + 1
y = 7
We get a result of 7, but we want 9 to be the actual output. So choice A is out.
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Repeat for choice C. Plug in x = 1
y = x^2 - 7x + 1
y = 1^2 - 7(1) + 1
y = 1 - 7 + 1
y = -5
We can eliminate choice C (since again we want a result of y = 9)
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Finally let's check choice D
y = x^2 - 7x - 1
y = 1^2 - 7(1) - 1
y = 1 - 7 - 1
y= -7
so choice D is off the list as well
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The only thing left is choice B, so it must be the answer. It turns out that plugging x = 1 into this equation leads to y = 9 as shown below
y = x^2 + 7x + 1
y = 1^2 + 7(1) + 1
y = 1 + 7 + 1
y = 9
And the same applies to any other x value in the table (eg: plugging in x = 3 leads to y = 31, etc etc).
