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:
-9x(5 - 2x) Distribute/multiply 9x into (5 - 2x)
(-9x)5 - (-9x)2x
-45x - (-18x²) 2 negative signs cancel each other out and become +
-45x + 18x² Your answer is A ( the first option)
The algebraic expression is:
E = t + 10
Answer:
Radius = 5 units
Step-by-step explanation:
Diameter of a circle = 10
Radius = diameter/2
Radius = 10/2
Radius = 5 units