Question

Solve by completing the square: x^2-6x+5=0

Answer 1

x^2 -6x +9 = -5 +9

Answer 2

What exactly does completing the square mean? What does it involve? What steps?

Answer 3

(x-3)^2 = 4

Answer 4

x^2+2px= x^2+2px+p^2 -p^2 = (x+p9^2 -p^2

Answer 5

Alisha101, where did the nines come from?

Answer 6

x^2+2px= x^2+2px+p^2 -p^2 = (x+p)^2 -p^2

Typo

Answer 7

thats the completing the square formula you move the number to the other side and complete the square

Answer 8

take the square root of 4 now to get -2 or 2

Answer 9

solve both equations x-3 = -2 or x-3 = 2

Answer 10

x = 1 or x = 5

Answer 11

estudier, What... is.... THAT!?!? Haha

Answer 12

That is the general procedure for completing the square without messing around with all those numbers.

Answer 13

move the 5 to other side so you have -5
now you need to find the perfect square completion to x^2 -6x + _____

Answer 14

if you put 9 in you can get the formula (x-3)^2 so you add 9 to both sides (what you do to one side you do to the other side

Answer 15

now condense and solve

Answer 16

Wouldn't you subtract 9?

Answer 17

estudier, what does the p represent in your formula?

Answer 18

In this case, -3

Answer 19

2*-3 = -6

Answer 20

Did you say there was a typo in that formula?

Answer 21

This post

"x^2+2px= x^2+2px+p^2 -p^2 = (x+p)^2 -p^2 Typo"

corrected the one two posts earlier.

Answer 22

So why is p=-3? Just so I know for different problems.

Answer 23

The problem will typically be presented as x^2 + bx...

p=b/2

The other thing u need to watch is if the problem is presented as ax^2 + when u need to divide through by a first.

Answer 24

That makes sense! Now just one more question! So for the formula, I solve for x, but do I write it all out at once? So it would be..... x^2+2(-3)x=x^2+2(-3)+(-3)^2-(-3)^2=(x+(-3)^2-(-3)^2????? How would I solve it all at once? Or do I take the formula apart somehow?

Answer 25

Also, for the option without the formula, I got x=(+-) 5

Answer 26

x^2+2(-3)x=x^2+2(-3)+(-3)^2-(-3)^2=(x+(-3)^2-(-3)^2?????

x^2+2(-3)x=(x+(-3)^2-(-3)^2 = (x-3)^2 - 9

After u have done a half dozen or so, u will be able to just do the thing without the middle bits on automatic...

Answer 27

Also, for the option without the formula, I got x=(+-) 5

So when u add the 5 u have

(x-3)^2 - 9 + 5 = (x-3)^2 -4 = 0 so

so x-3 = plus or minus 2.

x = -5 or 1.

Answer 28

Wouldn't it be positive 5? And thanks! I forgot about the (plus minus) part!

Answer 29

Yes, 5, sorry (as u may have noticed, my attention wanders with computations).

Answer 30

WOW, I ACTUALLY GOT IT! Thank you! :)

Answer 31

:-)

Answer 32

:-D