Question

In the figure given alongside, find :Angle ADC​

Answer 1

Answer:

A=40°

C=80°

D=50°

Step-by-step explanation:

first we have to use angle sum property by adding 40+100=140

so;180-140 = 40

Therefore A = 40°

and

at angle c. it will be 180-100

therefore C=80°

and

at angle D

we know A =40 and C 80

by adding 80+50 = 130°

and 180-130= 50

therefore D= 50°

Answer 2

Given :

∠ ABC = 40°

∠ ACB = 100°

∠ CAD = 50°

To find :

∠ADC

Solution :

For ∆ABC , let ∠BAC = x°

➝ x°+40° +100° = 180° [ sum of all angles of triangle is 180° ]

➝ x°+140° = 180°

➝ x° = 180°-140°

➝ x° = 40°

Therefore , ∠BAC = 40°

Now , ∠BAD = ∠BAC + ∠CAD

➝ ∠BAD = 40° + 50°

➝ ∠BAD = 90°

Now , we have to find out ∠ADC (or ∠ADB).

For ∆ADB, let ∠ADB be y°

➝ y°+40° +90° = 180° [ sum of all angles of triangle is 180° ]

➝ y°+130° = 180°

➝ y°= 180°-130°

➝ y°= 50°

Therefore, ∠ADC (or ∠ADB) = 50°

Answer : 50°