Anonymous asked in Science & MathematicsMathematics · 9 years ago

Please help me write a geometry proof about an isosceles triange!?

Please help me because I'm doing homework and this is the only question I'm having trouble with. I have to write a two column geometry proof.

Prove: If an isosceles triangle has an altitude from the vertex to the base, then the altitude bisects the vertex angle.

Given: Triangle ABC is isosceles; Segment CD is the altitude to base segment AB.

To Prove: Segment CD bisects Angle ACB

Plan: ?

Then there are two columns for the proof. One says statements and the other says reasons. There is a picture of the triangle where the base is AB with D in the middle between them. Then the altitude is from D to C and C is on the top. PLEASE help me!

2 Answers

  • 9 years ago
    Favorite Answer

    Triangle ABC is isosceles; Segment CD is the altitude to base segment AB. (Reason: Given)

    Segment AC = Segment BC (Reason: Def of isosolese triangle)

    Angle CAD = Angle CBD (Reason: Def of isosolese triangle)

    CD perpendicular to AB and CD bisects AB (Reason: Def of altitude)

    Segment AD = Segment DB (Def of midpoint)

    Angle ACD = Angle BCD (Side Angle Side)

    I think that should do it for ya

    Source(s): I'm an AP Calc student
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  • 3 years ago

    a) and b) are the line section that bisects HJ c) is "given" d) is the way you recognize they're congruent e) is the explanation issues are congruent to themselves f) is SSS (considering which you have not any records on any angles) g) is what facilitates you to break congruent triangles into corresponding areas i wish that factors you interior the ideal direction

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