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# Help Me With This Maths Problem Watch

1. Solve this to 2dp:

2x+3/x-4 - 2x-8/2x+1 = 1

Really don't understand this problem, what do I have to do? :L
2. (Original post by romansholiday)
Solve this to 2dp:

(2x+3)/(x-4) - (2x-8)/(2x+1)

Really don't understand this problem, what do I have to do? :L
you would be basically cross multiplying then due to the 2dp you would have to use the quadratic formula im assuming
3. I'm assuming you want the value of x
Open up the brackets and use the quadratic equation to work it out
4. (Original post by chrlhyms)
you would be basically cross multiplying then due to the 2dp you would have to use the quadratic formula im assuming
I forgot to add the = 1 on the end, does this make any difference?
5. (Original post by romansholiday)
Solve this to 2dp:

2x+3/x-4 - 2x-8/2x+1 = 1

Really don't understand this problem, what do I have to do? :L
cross multiply to get 2x+3(2x+1)- (2x-8)(x-4)/(X-4)(2x+1) = 1 , then times the 1 by the denominator to get 2x+3(2x+1) -(2x-8)(x-4)= (x-4)(2x+1)
6. (Original post by romansholiday)
I forgot to add the = 1 on the end, does this make any difference?
yeah because you would have to times the denominators by 1 and then rearrange
7. 1. Multiply by (x-4)(2x+1) so it's"
(2x+3)(2x+1) - (2x-8)(x-4)

2. Expand the brackets
4x^2+8x+3 - 2x^2-16x+32
= 2x^2-8x+35

3. Solve using the quadratic formula
a=2, b=-8, c=35
8. (Original post by romansholiday)
Solve this to 2dp:

2x+3/x-4 - 2x-8/2x+1 = 1

Really don't understand this problem, what do I have to do? :L
Step by step:
First you expand:
2x+3(2x+1)- (2x-8)(x-4)/(X-4)(2x+1) = 1
and then times the 1 by the denominator which equals to:
2x+3(2x+1) -(2x-8)(x-4)= (x-4)(2x+1)
9. (Original post by GlassyMarbles)
1. Multiply by (x-4)(2x+1) so it's"
(2x+3)(2x+1) - (2x-8)(x-4)

2. Expand the brackets
4x^2+8x+3 - 2x^2-16x+32
= 2x^2-8x+35

3. Solve using the quadratic formula
a=2, b=-8, c=35
Wouldn't it be 2x^2-8x-29? Instead of 2x^2-8x+35
10. (Original post by Kiniun)
Wouldn't it be 2x^2-8x-29? Instead of 2x^2-8x+35
No idea, did it in a rush. You're probably right though, I tend to make stupid mistakes during multiple-step maths questions.
11. (Original post by GlassyMarbles)
No idea, did it in a rush. You're probably right though, I tend to make stupid mistakes during multiple-step maths questions.

If you think that's a stupid step, you should see my 5x2=7 mistakes in exams loool
12. It got x = 25/31. Did anyone else get that?
13. (Original post by Kiniun)
If you think that's a stupid step, you should see my 5x2=7 mistakes in exams loool
Hahaha I get you, I wrote 26-16=8 in an exam once
14. (Original post by phat-chewbacca)
It got x = 25/31. Did anyone else get that?
I got the same!!! Turns out quadratic formula was unnecessary cuz the x^2s cancel out

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