Question

1. A. In figure 3.8, ZACD is an exterior angle of A ABC. ZB = 40°, ZA = 70°. Find the measure of ZACD.
2. In A PQR, ZP= 70°, ZQ = 65° then find 3. The measures of angles of a triangle are x°, (x-20)°, (x-40)º. Find the measure of each angle.
4. The measure of one of the angles of a triangle is twice the measure of its smalle angle and the measure of the other is thrice the measure of the smallest angle. Find th measures of the three angles.​

Answer 1

Answer:

4): Let three angles be x, y and z and the smallest angle be x. Then it is given

y=2x and z=3x

y+z=2x+3x=5x

Add x in both sides

x+y+z=5x+x=6x

180=6x

x=30

Therefore y=2x=2×30=60

z=3x=3×30=90

So three angles are 30, 60 and 90

Answer 2

Answer:

In figure 3.8, ZACD is an exterior angle of AABC. ZB =40°,ZA=70°.

the measure of ZACD = 110°

Step-by-step explanation:

In a triangle sum of all angles = 180°

ZABC + BAC+ ZACB = 180°

=> ZB+ZA+ ZACB = 180°

=> 40° +70° + ZACB = 180°

=> ZACB = 70°

ZACB + < ACD = 180° (straight line)

=> 70° + ACD = 180°

=> ACD= 110°

I hope this will helpful to you