Factoring Question

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Factoring Question

by sparkles3144 » Tue Mar 05, 2013 11:09 am
b) x^2 + y - 17 = 0
y = 2x

No. There is an x2 term. Even if 2x is substituted into
the first equation for y, 17 isn't a perfect square, so we should
expect the quadratic to have 2 distinct solutions.

I do know that it is not possible.
I just don't why they are referring to 17 and perfect square.

For example,
x^2 - 11x + 30 = 0
(x-5)(x-6)
Here, 30 is not perfect square, but still it can be factored into two distinct square.

In conclusion, my question is how is perfect square related to 17 in this question?

Thanks before hand!

Have a great week!
Last edited by sparkles3144 on Thu Apr 25, 2013 1:53 pm, edited 1 time in total.
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by hemant_rajput » Tue Mar 05, 2013 9:39 pm
sparkles3144 wrote:b) x^2 + y - 17 = 0
y = 2x

No. There is an x2 term. Even if 2x is substituted into
the first equation for y, 17 isn't a perfect square, so we should
expect the quadratic to have 2 distinct solutions.

I do know that it is not possible.
I just don't why they are referring to 17 and perfect square.

For example,
x^2 - 11x + 30 = 0
(x-5)(x-6)
Here, 30 is not perfect square, but still it can be factored into two distinct square.

In conclusion, my question is how is perfect square related to 17 in this question?

Thanks before hand!

Have a great week!
here is an advice

Whenever you post something on forum, please post complete question so that it is actually easy to comprehend in precise manner.
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.