Question

[8.06] Which polynomial is a perfect square trinomial?

49x2 − 28x + 16

4a2 − 20a + 25

25b2 − 20b − 16

16x2 − 24x − 9

Answer 1

is it a?

Answer 2

Or b?

Answer 3

I will become a fan to the person who gives me the right answer to this!

Answer 4

lol i will give me a sec to do the math

Answer 5

:)Thx, of course I will

Answer 6

For each answer choice, do this

take the square root of the first and last coefficients

say we're looking at choice A

the square root of 49 is 7, the square root of 16 is 4.

Multiply these two numbers together to get 7*4 = 28, then double it to get 2*28 = 56


Since this result of 56 is NOT equal to the middle coefficient of 28, this means that choice A is NOT a perfect square (so you can eliminate choice A)

Answer 7

Hmm..ok...let's see. :)

Answer 8

b?

Answer 9

why

Answer 10

Well, I guess because 4 is a perfect square root.

Answer 11

the square root of 4 is what?

Answer 12

sorry, is factorable,so you get...
(2a - 5)^2

Answer 13

?

Answer 14

yes good, hopefully you see how to get that?

Answer 15

yes, I do now! Thx! :D

Answer 16

np