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a couple of maths questions...help needed (1 Viewer)

tabsheer

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heyy guyz

need help doin a couple of questions from a past paper in my school
can any1 plz solve these with showing workin so i get how to do it coz im really confused and it doesnt work out wenever i try


  1. Solve t = ½ square root a/L for L
  2. Factorise: a) 2x² -3x -4
b) x² + 5x + 10

Thanx in advance



 

M@ster P

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For Question 2a and 2b you use the quadratic formula
 

Drongoski

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Q1: don't understand question

Q2: are you sure questions correct ?
 
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tabsheer

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i dont understand Q 1 either =S it was written like that


yeah question 2 is correct i tried and it didnt come -_- ...cnt use quadratic formula coz its factorising not finding x
 

Drongoski

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Where do you get these questions from? Q2 can't be done.
 

undalay

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i dont understand Q 1 either =S it was written like that


yeah question 2 is correct i tried and it didnt come -_- ...cnt use quadratic formula coz its factorising not finding x
You can use quadratic formula to factorise.

and then u get
x=a,b

then factors would then just be (x-a)(x-b)
 

addikaye03

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heyy guyz

need help doin a couple of questions from a past paper in my school
can any1 plz solve these with showing workin so i get how to do it coz im really confused and it doesnt work out wenever i try


  1. Solve t = ½ square root a/L for L
  2. Factorise: a) 2x² -3x -4
b) x² + 5x + 10

Thanx in advance



a)

t=1/2rt(a/L)

2t=rt(a/L)

4t^2=a/L

L=a/4t^2

2b)

x^2+5x+10

(x+5/2)^2-15/4

[(x+5)-rt15/4][(x+5)+rt15/4]

Are they right... those Q are just fucking stupid.
 
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Timothy.Siu

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You can use quadratic formula to factorise.

and then u get
x=a,b

then factors would then just be (x-a)(x-b)
u cant do that for the first one, well u can but u cud get it wrong

Factorise: a) 2x² -3x -4
2(x^2-3/2x-2)=2(x-3/4)^2-17/4=2(x-3/4+root17/2)(x-3/4-root17/2)
b) x² + 5x + 10
no solution
 
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GUSSSSSSSSSSSSS

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yea lookin at ur graduation year....q2b has no solutions and so cannot be factorised
 

Drongoski

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Hey GUS13.

You may find my posting under "Which one do you prefer .. " more interesting ? than dealing with these problems.
 
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shell.q

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1. as stated above
t=1/2rt(a/L)

2t=rt(a/L)

4t^2=a/L

L=a/4t^2

2a. 2(x^2-3x-4) 2(x+1)(x-4)
i.e x = -1, 4
thts how i would do tht

b. this is where i would use the quadratic formula
 

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