Question

Determine which polynomial is a perfect square trinomial.
25b2 - 15b + 9
16x2 - 56x + 49
9a2 - 20a - 25
25x2 - 40x - 16

Answer 1

Do u understand or are you completely lost?

Answer 2

completely lost

Answer 3

can any one help me

Answer 4

Answer: 16x2 − 56x + 49

Answer 5

This is how you check it.

A perfect square binomial is of the form:

\(a^2 + 2ab + b^2 = (a + b)^2 \)

or

\(a^2 - 2ab + b^2 = (a - b)^2 \)

Notice that in either case, for the trinomial the first term, a^2, is the square of a. The third term of the trinomial, b^2, is the square of b. The second term, 2ab, or -2ab is the product of 2, a, and b or -b.

Answer 6

thanks guys

Answer 7

welcomes :)

Answer 8

The practical way of using the above information is like this.

When you are given a trinomial to determine if it is a perfect square trinomial, follow these steps:

1. Is the first term the square of something? If so what?
2. Is the third term the square of something? If so what?
3. Is the second term 2 times the first term times the second term you found in steps 1 and 2 above?

If all answers are yes, then it is a perfect square trinomial.
If the answer to any of these questions is no, then it is not a perfect square trinomial.

Answer 9

Look at choice A:
25b^2 - 15b + 9
1. 25b^2 is the square of 5b
2. 9 is the square of 3 and -3
3. Is 15b equal to 2 * 5b * 3 or 2 * 5b * (-3) ?
2 * 5b * 3 = 30b; 2 * 5b * (-3) = -30b
The answer is no, so this is not a perfect square trinomial.