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# What am I doing wrong here?

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1. Okay I have this question, but I am getting the wrong answer, where am I going wrong?

1 1/4 (4-2x) = 5/14 (6x+1)

So first I make it look nicer

5 (4-2x) / 4 = 5 (6x+1) / 14

Then I cross multiply

70(4-2x) = 20(6x+1)

Then multiply out he brackets

280-140x = 120x + 20

And then rearrange

140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
2. (Original post by theoallen)
Okay I have this question, but I am getting the wrong answer, where am I going wrong?

1 1/4 (4-2x) = 5/14 (6x+1)

So first I make it look nicer

5 (4-2x) / 4 = 20 (not 5) (6x+1) / 14

Then I cross multiply

70(4-2x) = 20(6x+1)

Then multiply out he brackets

280-140x = 120x + 20

And then rearrange

140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
You didn't multiply the right hand side by 5
3. (Original post by theoallen)
Okay I have this question, but I am getting the wrong answer, where am I going wrong?

1 1/4 (4-2x) = 5/14 (6x+1)

So first I make it look nicer

5 (4-2x) / 4 = 5 (6x+1) / 14

Then I cross multiply

70(4-2x) = 20(6x+1)

Then multiply out he brackets

280-140x = 120x + 20

And then rearrange

140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
Is x=1 the answer by any chance?

You seem to have done your final rearranging wrong.
4. (Original post by theoallen)

280-140x = 120x + 20

And then rearrange

140x-120x = 280+20 = 300, but that's not the answer, what have I done wrong?
That's almost right. You should use more steps:

280 - 140x = 120x + 20

Move the 140x over (it becomes a +)

280 = 140x + 120x + 20

Move the 20 over (it becomes a -)

280 - 20 = 140x + 120x

Simplify and solve.
5. (Original post by Axel Johann)
You didn't multiply the right hand side by 5
He didn't multiply the left hand side by 5 either then... he just converted from
6. (Original post by Axel Johann)
You didn't multiply the right hand side by 5
Check again. You seem to have misunderstood.

(Original post by natninja)
Is x=1 the answer by any chance?
Yep.
7. (Original post by natninja)
He didn't multiply the left hand side by 5 either then... he just converted from
(Original post by Zacken)
Check again. You seem to have misunderstood.

Yep.
Ohh i didnt see taht 1 haha

whoops
8. (Original post by Axel Johann)
You didn't multiply the right hand side by 5
Am I meant too? Why would I multiply it by 5?
9. (Original post by theoallen)
Am I meant too? Why would I multiply it by 5?
Nah don't worry, i was wrong.
10. (Original post by theoallen)
Am I meant too? Why would I multiply it by 5?
Look at the other posts on the thread.

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