Determine if x2 + 9x + 20 is a perfect square trinomial and factor.

2 answers:

7 0

It's not a perfect-square trinomial.

A perfect-square trinomial is of the form $a^2 \pm 2ab+b^2=(a+b)^{2}$ .

If that looks confusing, just realize that the first and third terms need to be perfect squares (e.g., 16, because it is the square of 4, or 81, because it is the square of 9), and the middle term needs to be twice the product of a and b.

So $x^{2}$ is a perfect square equal to x times x. Is 20 a perfect square? Can you think of an integer whose square is 20? No, so 20 is not a perfect square. We are done.

The correct answer is D.

professor190 [17]4 years ago

4 0

The answer would be D

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PLEASE HELP!!!! I WILL GIVE BRAINLIEST AND LOTS OF POINTS!!! Please provide an explanation and answer only if you know the answe

weeeeeb [17]

Answer:

x = 29

Step-by-step explanation:

If the lines are parallel

< CBA = < DAB due to the fact that they are alternate interior angles

42 = DAB

We also know that

DAB + BAC + CAE = 180 since they form a straight line

Substituting the given values

42+ 109 + x = 180

Combine like terms

151 + x = 180

151+x-151 = 180-151

x = 29

3 0

4 years ago

How do you do this problem?

Vadim26 [7]

Answer:

Your answer is absolutely correct

Step-by-step explanation:

The work would be as follows:

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