Anonymous
Anonymous asked in Science & MathematicsMathematics · 9 years ago

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!

Relevance
• 9 years ago

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