*2 values of x for perpendicular vectors

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SUMMARY

The discussion centers on finding the values of \( x \) for which the vectors \( \left(\frac{2x}{x-3}\right) \) and \( \left(\frac{x+1}{5}\right) \) are perpendicular. The quadratic equation derived is \( 2x^2 + 7x - 15 = 0 \), yielding solutions \( x = -5 \) and \( x = \frac{3}{2} \). While \( x = -5 \) is confirmed to work, there was initial confusion regarding \( x = \frac{3}{2} \), which was later validated as a proper solution after addressing a calculation error.

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karush
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The vectors $$\left(\frac{2x}{x-3}\right)$$ and $$\left(\frac{x+1}{5}\right)$$ are $$\perp$$ for $$2$$ values of $$x $$

what is the quadratic equation which the 2 values of x satisfy

well I got $$2x^2+7x-15$$ which gives $$x=-5$$ and $$x=\frac{3}{2}$$
-5 seems to work but
$$\frac{3}{2}$$ doesn't or is there another way to do this.

thanks ahead,
 
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Re: 2 values of x for perpendicular vectors

karush said:
The vectors $$\left(\frac{2x}{x-3}\right)$$ and $$\left(\frac{x+1}{5}\right)$$ are $$\perp$$ for $$2$$ values of $$x $$

what is the quadratic equation which the 2 values of x satisfy

well I got $$2x^2+7x-15$$ which gives $$x=-5$$ and $$x=\frac{3}{2}$$
-5 seems to work but
$$\frac{3}{2}$$ doesn't or is there another way to do this.

thanks ahead,

Hi karush! :)

What is the reason you think $x=\frac 3 2$ does not work?
It is a proper solution.
 
Re: 2 values of x for perpendicular vectors

when I plugged $$\frac{3}{2}$$ in the slopes didn't seem $$\perp$$
 
Re: 2 values of x for perpendicular vectors

karush said:
when I plugged $$\frac{3}{2}$$ in the slopes didn't seem $$\perp$$

Well... which vectors do you get if you plug it in?
 
Re: 2 values of x for perpendicular vectors

OK found my error...
 

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