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xsquared-2x-1=0

multiplexing-gamer

Give your solutions to 2 decimal places.
I'm guessing you start of like this:
(x )(x )

Reply 1

bigAsh

Original post by multiplexing-gamer

Give your solutions to 2 decimal places.
I'm guessing you start of like this:
(x )(x )

Use the quadratic formula :smile:

Reply 2

Gemini92

Original post by multiplexing-gamer

Give your solutions to 2 decimal places.
I'm guessing you start of like this:
(x )(x )

Use the quadratic formula

Reply 3

sweety0471

try the formula
http://www.google.co.uk/imgres?imgurl=http://2.bp.blogspot.com/_V8KsSIiGjBk/SsACMEj73KI/AAAAAAAAFIU/vNtErLdchMw/s1600/Quadratic%252BFormula.gif&imgrefurl=http://howto1.blogspot.com/2010/02/how-to-write-in-quadratic-formula.html&usg=__6nB5rpmEqmGVqIb1GBzvAgGmWBA=&h=265&w=378&sz=3&hl=en&start=0&sig2=gxUGWHm8u1EhTA2bckobsg&zoom=1&tbnid=qM-pgrWi6WNcjM:&tbnh=156&tbnw=216&ei=aeKITesrg4CFB8OR4ccN&prev=/images%3Fq%3Dquadratic%2Bformula%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1R2SUNC_enGB360%26biw%3D1342%26bih%3D490%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=474&vpy=125&dur=686&hovh=188&hovw=268&tx=173&ty=135&oei=aeKITesrg4CFB8OR4ccN&page=1&ndsp=12&ved=1t:429,r:2,s:0

Reply 4

sweety0471

where a - number in front of x^2, b is number infront of x and c is the last number

complete the square

Oh yeh thanks guys

quadratic formula, it will be at the fron of the paper, but you have to give the + and the - values

Reply 8

dknt

Original post by multiplexing-gamer

Give your solutions to 2 decimal places.
I'm guessing you start of like this:
(x )(x )

The "solutions to 2dp" gives you a clue that it won't factorise with integer values. You can complete the square or use the quadratic formula. Since they don't want an exact form, putting everything into the quadratic formula will probably be faster.

Reply 9

MostCompetitive

Original post by multiplexing-gamer

Give your solutions to 2 decimal places.
I'm guessing you start of like this:
(x )(x )

Use

x=\frac {-b \pm \sqrt{b^2-4ac}} {2a}

a = the number in front of the

x^2

= 1
b= -2 (the number in front of the x) so -b = 2
c= -1 ( the last number)

the plus-minus sign means that there are two solutions (use the plus once and minus once)

The mathematical term for 'in front of' is coefficient btw.