Stuck with finding variables using the distance equation

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Solar_blaze

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Apr 20, 2015
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I have been trying and got stuck again
It says "find a coordinate point on the Y axis which it's distance from the point (8.19) is 10.
I tried this using the distance equation
10=root (8-0)^2+(19-y)^2
10=root 64+361-38y+y^2
And than I got stuck with 100=root 425-38y+y^2
Is this correct what to do next ?
 
I don't know how to make/write the matmatic symbol of the "root " symbol on the tablet , also is it right ?
 
Solar_blaze said:
I don't know how to make/write the matmatic symbol of the "root " symbol on the tablet , also is it right ?
Click to expand...
You have completely missed the point! Why have root there at all?

If \(\displaystyle 10=\sqrt{64+361-38y+y^2}\) then \(\displaystyle 100=425-38y+y^2\).

You had better take some time off and review elementary algebra.
 
I understood that there is no need for root misunderstanding of me on the definitions of the mathematics I did what you said 100=425-38y+y^2
than 325-38y+y^2 =0
Now I am stuck
 
This is more complex and apparently I didn't get it
I am stuck on those exorcises for a whole day now
 
Solar_blaze said:
Is this right? I simplified and got it (Y-13)(Y-25)
Click to expand...

You had this equation:
y2 - 38y + 325 = 0

And then, apparently you factored the left side into (y - 13)(y - 25).....but this is NOT the answer. You can write your equation as

(y - 13) (y - 25) = 0

And now you can use the Zero-Product Property....if a*b = 0, then either a = 0 or b = 0. So, if
(y - 13)*(y - 25) = 0, then

y - 13 = 0 or y - 25 = 0
so,
y = 13 or y = 25

And NOW you can find the two points on the y-axis which satisfy the conditions of the problem....(HINT: each is of the form (0, y)......)
 
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