Answer:
m∠ABC= 80°, m∠BDC= 90°
Step-by-step explanation:
If m∠ABD = 40°, then add 40°+40° to get m∠ABC because AB ≅ BC, meaning their angles would be congruent.
For m∠BDC, just look at the picture and deduce that it's a 90 degree angle.
Answer:
m∠ABC=80° and m∠BDC=90°
Step-by-step explanation:
Given the ΔABC in which AB ≅ BC, m∠ABD = 40° and BD is median of ΔABC.
we have to find the measure of angle ∠ABC and ∠BDC.
As the median of isosceles triangle split the angle at the vertex into two equal parts i.e ∠ABC is twice the angle ∠ABD
⇒ [tex]\angle ABC=2\angle ABD[/tex]
[tex]\angle ABC=2\times 40=80^{\circ}[/tex]
Also the median of isosceles triangle is perpendicular to the opposite side i.e to the base. Here, BD is perpendicular to AC
⇒ ∠BDC=90°
Therefore, the measure of angle ABC and BDC is 80° and 90° respectively.