Question

Which of the following statements is false?

A. 3x^2 + 4x^2 = 7x^4

B. 3x^2 • 4x^2 = 12x^4

C. (3x^3)^2 = 9x^6

D. –3^2 = –9

Answer 1

Is D the correct answer?

Answer 2

Yes.

Answer 3

Why? Well because 3*2 is equal to what?

Answer 4

OH WAIT. NO.

Answer 5

I thought it said 3*2. >_>

Answer 6

-3^2 is another way of saying -3 * -3.
3 *3 = 9
A negative multiply a negative is a positive.
So it's a positive 9 or just 9.

Answer 7

So which statement is false?

Answer 8

Guess and check.

Answer 9

Let's try C. C. (3x^3)^2 = 9x^6
What does C. (3x^3)^2 become?

Answer 10

9x^5?

Answer 11

Well let see. Another way of writing that is:
C. (3x^3)(3x^3)
3 * 3 = 9
x^3 * x^3= x^6

Answer 12

So that is true. Though that's not the correct answer.
Let's try B:
B. 3x^2 • 4x^2 = 12x^4

What does 3x^2 • 4x^2 give you?

Answer 13

D is right for sure

Answer 14

D is also right
\[(3x^3)^2 = 9x^6\] is true

Answer 15

the wrong one is the first one
\[ 3x^2 + 4x^2 = 7x^4\]

Answer 16

for example, if \(x=10\) then \(300+400=700\) not \(300+400=70000\)

Answer 17

So isn't the answer either A or D?

Answer 18

no

Answer 19

only A is wrong

Answer 20

I am so confused right now!

Answer 21

why is A wrong?

Answer 22

@GoldPhenoix you made a mistake here
-3^2 is another way of saying -3 * -3.

Answer 23

in fact \(-3^2=-3\times 3=-9\)

Answer 24

A is wrong because when you add, you do not add exponents

Answer 25

Really?! I never knew! o_o

Answer 26

3 apples and 4 apples is 7 apples
3 x squared and 4 x squared is 7 x squared

Answer 27

that is what i was trying to explain when i said " put \(x=10\)"
if \(x=10\) then \(3x^2=300\) and \(4x^2=400\) and when you add you get
\[700=7\times 10^2\] not \(7\times 10^4\)

Answer 28

in other words,
\[3x^2+4x^2=7x^2\]

Answer 29

@GoldPhenoix you did so know that
suppose you were asked to compute
\[50-3^2\] what would you get?

Answer 30

50-9=41

Answer 31

right, so you knew that \(-3^2=-9\) or else you would have said
\[50-3^2=50+9=59\] which is silly

Answer 32

Oh, I see.

Answer 33

so A is wrong...

Answer 34

Therefore, A is the correct answer in your question.

Answer 35

yeah... thanks!:)