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# Why is this happening? Watch

1. This should be simple...

A = 0.5, yx^2/2a = 10, and yx/a = 50

If I substitute a in first, I get a different answer to when I substitute it in at the end. Here's my logic: 2a = 1 so yx^2=10 and yx = 100, then divide one by the other and you get x = 1/10, 0.1

however,

if you divide one by the other with a, you get x/2 = 1/5, so x = 0.4

What's going on?
2. (Original post by IL9)
This should be simple...

A = 0.5, yx^2/2a = 10, and yx/a = 50

If I substitute a in first, I get a different answer to when I substitute it in at the end. Here's my logic: 2a = 1 so yx^2=10 and yx = 100, then divide one by the other and you get x = 1/10, 0.1

however,

if you divide one by the other with a, you get x/2 = 1/5, so x = 0.4

What's going on?
Could you use latex or at least brackets

Oh, and is A the same as a?
3. (Original post by IL9)
This should be simple...

A = 0.5, yx^2/2a = 10, and yx/a = 50

If I substitute a in first, I get a different answer to when I substitute it in at the end. Here's my logic: 2a = 1 so yx^2=10 and yx = 100, then divide one by the other and you get x = 1/10, 0.1

however,

if you divide one by the other with a, you get x/2 = 1/5, so x = 0.4

What's going on?
If I'm right you're saying that the 2nd method is to divide by a?
This isn't true.
4. (Original post by IL9)
Here's my logic: 2a = 1 so yx^2=10 and yx = 100
yx does not equal 100.

yx/a=50 so yx = 50a = 25
5. A is the same as a, it is y times x squared, to be clear. The second method I'm dividing. One equation by the other, just like the first, but I'm leaving a in the equations rather than putting its value of 0.5 in. Obviously they cancel when divided by each other, because the a is on the denominator for both. Now can you explain why there are different answers?
6. (Original post by ghostwalker)
yx does not equal 100.

yx/a=50 so yx = 50a = 25

Got it, knew it was something stupid, thanks.

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