Question

1. m∠ABD=50°, m∠DBC=40° Given 2. m∠ABD+m∠DBC=m∠ABC Response area 3. Response area Substitution Property of Equality 4. Response area Simplifying 5. ∠ABC is a right angle. Response area 6. △ABC is a right triangle. Definition of right triangle

Answer 1

Answer:

<abd+<dbc=<Abc

50+40=90

triangle abc is a right angled triangle being one angle 90 degree