Question

(5-x)^1/2 = x+1 (show steps plz!)

Answer 1

How about I take you through it step by step instead?

Answer 2

sounds good to me.

Answer 3

Okay, so it's easier if you get rid of the 1/2 exponent, so square both sides.

Answer 4

i did that and got 5-x= x^2+2x+1

Answer 5

then set everything equal to 0

Answer 6

0=x^2+3x-4

Answer 7

factor that

Answer 8

everything after is a blurr

Answer 9

ok

Answer 10

ummm yeah. i have no idea.

Answer 11

Quadratic formula....

Answer 12

all right.
so when you factor you're going to get (x+y)(x-z)=0 where y and z are numbers, possibly the same number. You know you're going to subtract one of them and add one of them because if you look at the number that has no x's in it (-4) you subtract it.

Did that much make sense?

Answer 13

You can also use the quadratic formula, but I find factoring it easier.

Answer 14

Factoring is easier, but for people who can't do that sort of factoring in their head, the quadratic formula is handy.

Answer 15

Or at least it's easier if you understand factoring, which is definitely something you learn by practicing.

Answer 16

Exactly!

Answer 17

is that -(b)sqrt(b^2)-4(a)(c)/ 2(a)?

Answer 18

That's true, I completely agree with you, Harwin. Sorry, slow typer apparently!

Answer 19

(-b + sqrt(b^2 - 4ac))/2a
and
(-b - sqrt(b^2 - 4ac))/2a

Answer 20

oh whoops yeah for got the +-

Answer 21

Anyway, snooozzzzze knows how to get you through it. I'll give the show back to him.

Answer 22

haha her, but that's ok. :)

Do you want to use the quadractic formula, or try factoring?

Answer 23

so does \[-11+-\sqrt{73}/8\] sound like its on the right track?

Answer 24

Oh sorry. English really needs a genderless pronoun other than "it"....

Answer 25

ha

Answer 26

Use the quadractic formula on this equation:
0=x^2+3x-4

Answer 27

oh shoot sorry i was looking at another equation

Answer 28

That's very true. Not sure calling me it would have been better, but in any case it's not a big deal at all.

RedCarr: No problem at all. Just try again with the right equation this time.

Answer 29

how about \[-3+-\sqrt{57}/2\]?

Answer 30

I'm not sure how you got the 57, but it's wrong.

Answer 31

also, when you do it, make sure that you know that the 2 is over everything, not just the squareroot part.

Answer 32

in place of the 57 would it be 25?

Answer 33

that looks right to me.

Answer 34

so x=1 and X=-8?

Answer 35

No, this is what you should get:
(−3+5)/2
(−3-5)/2

Answer 36

? i meant -4 but why the parenthesis?

Answer 37

because otherwise you'd have written -3+5/2 which would simplify to -3+2.5=-0.5

Answer 38

but yes, -4 and 1 is correct.

Answer 39

except look at your original problem to see if they work.

Answer 40

do you have a graphing calc with you? if you do plug in \[-3+\sqrt{25}\]

Answer 41

because actually only one of them works in that case.

Answer 42

I don't have a calculator, but I can visualize it.

Answer 43

yeah only 1 does not the -4

Answer 44

right, and that's because when we started the problem we squared both sides, which gave us the extra answer.

Answer 45

well when i plugged it in my answer was 2. then i divided that 2 by 2 to get 1 which is the only answer.

Answer 46

I'm sorry, could you restate that? I'm not really sure what you mean.