Help?(: {Find x & y.}
i worked it out partly.. and got this as my answer.(: Hope it helps.
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k
That gives 5y = 12x
The product of the lengths of the segments of one chord equals the product of the lengths of the segements of the other chord.
In english please? ..you lost me there.
Now look at right triangle TRV, with right angle R.
ok
This is a chord. |dw:1372785948886:dw|
Now you have a circle with two intersecting chords. |dw:1372785997147:dw|
k
One chord has two segments of lengths a and b. The other chord has segments of lengths c and d. |dw:1372786042595:dw|
ok?
.sure?
can we plug in the numbers from the problem? cuz im still not getting it..
I'm trying to first explain the reason why you can write the equations. You have two variables, x and y. You need two equations. We're going to use the chords to get one equation. We're going to use the right triangle to get the second equation.
k
In your problem, one chord has segments of lengths 5 and y. The other chord has segements of lengths 12 and x. That means 12x = 5y This is our first equation.
Now for the second euquation, we use the right triangle TRV with right angle R.
One leg measures 15. One leg measures y. The hypotenuse measures x + 9.
Now we use the Pythagorean Theorem using the lengths of the sides to get our second equation. 15^2 + y^2 = (x + 9)^2
Now we have our two equations. We need to solve them simultaneously for x and y.
that is necessarily not the hypotenuse
does not say SR is passing through the center
???
@dan815 You are correct.
:)
So was my answer wrong, or not?
I was thinking SR is a diameter, but it does not state it is anywhere.
yeah i thought so at first too, it would have this a lot simpler
Soo.....?
That means we need a different method of getting the second equation. The first equation is still good, 12x = 5y. Now let's work on the second equation using the segments of the tangent and secant TQ.
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The secant is made up of two segments. The external part (outside the circle) and the internal part (inside the circle).
The relaitionship between the lengths of the segments is: (whole secant) * (external segment of the secant) = (tangent)^2
In our problem, the entire secant is 9 + x + 12 = x + 21 The external part of the secant is 9 The tangent is 12
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doesnt it make you stare at it
theres some crazy symmetry going on in that picture
Ok im really confused now.. Can i just get a simple yes or no to my question? Was it wrong or not? Ive spent over 20 minutes on this i have to move on to other problems. Thanks for trying guys.
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