ABC is an isosceles triangle with BA=BC
D lieson AC
ABD is an isosceles triangle with AB=AD
Angle ABD=72
Show that triangle BCD isosceles
You must give a reason for each stage of your working

Explanation:

1. ∠BAC≅∠BCA, ∠ABD≅∠ADB; Reason: definition of isosceles triangles

2. ∠ABD +∠BAC +∠ADB = 180°; Reason: sum of internal angles is 180°

3. ∠BAC = 180° -2(∠ABD) = 36°; Reason: Subtraction and substitution properties of equality

4. ∠BAC +∠BCA +∠ABC = 180°; Reason: sum of internal angles is 180°

5. ∠BCA = 180° -2(∠BAC) = 108°; Reason: Subtraction and substitution properties of equality

6. ∠ABD +∠DBC = ∠ABC; Reason: Angle sum theorem

7. ∠DBC = ∠ABC -∠ABD = 108° -72° = 36°; Reason: Subtraction and substitution properties of equality

8. ∠BCA = ∠BAC = 36°; Reason: Substitution property of congruence

9. ΔBCD is isosceles; Reason: Base angles DBC and BCA are congruent.

There may be extra steps involved if you separately use subtraction and substitution properties of equality, or if you separately claim congruence of angles and equality of their measures. We have assumed that the definition of "isosceles triangle" includes the fact of equal side lengths and equal base angles.

im not sure

step-by-step explanation:

the correct option is 2.

step-by-step explanation:

according to the given information triangle abc is a right angle triangle with right angle at a. segment ab is 5 and segment ac is 7. point d is on segment bc and angles adb and adc are right angles.

it is given that triangles abd, cad, and cba are similar.

two triangles are similar if their corresponding sides are proportional.

in triangle cba, using pythagoras theorem

                      )

triangle abd and cba are similar,

                            (2)

triangle cad and cba are similar,

                      )

using (1), (2) and (3), we get

hence proved.

therefore option 2 is correct.