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Geometry please help.

Geometry please help.-example-1
User Ssougnez
by
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1 Answer

4 votes

Answer:

CD = 16

Explanation:

We can see that both AC and AB are radii. This means that they are equal, so AC = AB = 17. From segment addition postulate we can say AB = AE + BE

We are given BE, and we found the length of AB, so we can substitute and solve for AE:

AB = AE + BE

17 = AE + 2

AE = 15

Since we are given that AB is perpendicular to CD, ∠AEC would be a right angle, making ΔAEC a right triangle.

Now, we can use the pythagorean theorem to find the length of CE.

a^2 + b^2 = c^2

We are given the hypotenuse, c or AC in this case, and one leg, b, or AE in this case. We can plug in the values we are given:

CE^2 + AE^2 = AC^2

CE^2 + 15^2 = 17^2

CE^2 + 225 = 289

CE^2 = 64

CE = 8

Now, if a chord is perpendicular to a radius(AB in this case) we can say that it is split in half by the radius. This is basically saying that CE = DE = 8.

Again, using segment addition postulate, we can say:

CE + DE = CD

CD = 8 + 8

CD = 16

User Tomis
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3.4k points