Question

what value completes the square for the expression? x^2-16x
Would it be 64 or -64?

Answer 1

@agent0smith

Answer 2

I think its -64

Answer 3

To complete the square for

ax^2 + bx

find (b/2)^2

Answer 4

^notice the brackets.

Answer 5

yea I see

Answer 6

So what do you think it is?

Answer 7

So Im incorrect on my answer btw?

Answer 8

^yes.

Easiest way is to ignore the negative, if b is negative.

That saves time with squaring ANY numbers, eg if you're squaring -24, just square 24 on a calculator, it saves time

Answer 9

so it'll be 32?

Answer 10

Wait, how'd you get 32? Divide b by 2, then square it.

Answer 11

(b/2)^2 is not the same as b^2/2

Answer 12

the answer choices are:
-64
64
32
-32
Im 95% sure its -64

Answer 13

I may be wrong though.

Answer 14

Let's go back to this. (b/2)^2

b is -16, right? So put that in there ^^

(-16/2)^2
(-8)^2

which is...

Answer 15

64

Answer 16

so its positive 64?

Answer 17

Yep :)

Answer 18

thank you (:

Answer 19

Welcome :)