maths question answer please
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Answers
Step-by-step explanation:
Here,
- (Y+20)° + (2y +30)° + (y+10)°=180°(L.P.P)
- Y + 2y + y +20+30+10 =180°
- 4y+60 =180°
- 4y =180 - 60°
- Y =120/4°
- Y = 30°
Now,
(Y+20)° = 30° +20° = 50°
2Y° + 30° = 2×30° + 30° = 90°
Y° + 10° = 30° + 10°=40°
Provided that:
- AOB is a straight line.
To find:
- Find ∠AOC, ∠BOD and ∠BOC
Solution:
~ According to the figure,
- AOC = (y + 20)°
- BOC = (2y+30)°
- BOD = (y+10)°
~ According to the question,
- AOB is a straight line
Knowledge required: If any angle is on a straight line then it's sum is always 180 degrees. Therefore,
→ AOC + BOC + BOD = 180° (∵ Linear Pair)
→ (y + 20)° + (2y+30)° + (y+10)° = 180°
→ y + 20 + 2y + 30 + y + 10 = 180°
→ y + 2y + y + 20 + 30 + 10 = 180°
→ 1y + 2y + 1y + 20 + 30 + 10 = 180°
→ 4y + 20 + 30 + 10 = 180°
→ 4y + 60 = 180°
→ 4y = 180° - 60°
→ 4y = 120°
→ y = 120/4
→ y = 30°
We get the value for y as 30 degree
~ Now let us substitute the value of y in the each of three angles
Let us put y in the angle ∠AOC first
→ y + 20°
→ 30° + 20°
→ 50° is the measure of ∠AOC
Now let us put y in the angle ∠BOD
→ y + 10°
→ 30° + 10°
→ 40° is the measure of ∠BOD
Now let us put y in the angle ∠BOC
→ 2y + 30°
→ 2(30) + 30
→ 60° + 30°
→ 90° is the measure of ∠BOC