Home
Class 7
MATHS
In a triangleABC, if 2 /A = 3 /B = 6/C, ...

In a `triangle`ABC, if 2 `/_A` = 3 `/_`B = 6`/_`C, then `/_B` = ? `

A

`30^(@)`

B

`90^(@)`

C

`60^(@)`

D

`45^(@)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of angle B in triangle ABC given the relationships between the angles. ### Step-by-Step Solution: 1. **Set Up the Relationships**: We are given that: \[ 2 \angle A = 3 \angle B = 6 \angle C \] Let's denote \( \angle B \) as \( B \). Then we can express \( \angle A \) and \( \angle C \) in terms of \( B \): \[ \angle A = \frac{3}{2}B \] \[ \angle C = \frac{1}{2}B \] 2. **Use the Triangle Sum Property**: The sum of the angles in a triangle is always \( 180^\circ \): \[ \angle A + \angle B + \angle C = 180^\circ \] Substituting the expressions for \( \angle A \) and \( \angle C \): \[ \frac{3}{2}B + B + \frac{1}{2}B = 180^\circ \] 3. **Combine Like Terms**: Combine the terms on the left side: \[ \left(\frac{3}{2}B + B + \frac{1}{2}B\right) = \left(\frac{3}{2}B + \frac{2}{2}B + \frac{1}{2}B\right) = \frac{6}{2}B = 3B \] So we have: \[ 3B = 180^\circ \] 4. **Solve for Angle B**: Divide both sides by 3: \[ B = \frac{180^\circ}{3} = 60^\circ \] 5. **Conclusion**: Therefore, the value of angle B is: \[ \angle B = 60^\circ \]
Promotional Banner

Topper's Solved these Questions

  • CONSTRUCTIONS

    RS AGGARWAL|Exercise TEST PAPER|8 Videos
  • CONSTRUCTIONS

    RS AGGARWAL|Exercise TEST PAPER (M.C.Q)|7 Videos
  • CONSTRUCTIONS

    RS AGGARWAL|Exercise EXERCISE B|10 Videos
  • CONGRUENCE

    RS AGGARWAL|Exercise EXERCISE|18 Videos
  • DECIMALS

    RS AGGARWAL|Exercise TEST PAPER-3(D)|5 Videos

Similar Questions

Explore conceptually related problems

In a /_\ ABC ,if 2 /_A = 3 /_B = 6 /_C , then /_B = ?

In a Delta ABC, if 2 /_A = 3 /_B = 6 /_C then calculate /_A, /_B and /_C .

In a triangle ABC, if /_ A gt /_ B gt /_C and the measures of /_A , /_B and /_ C in degrees are integers, then the least possible value of /_ A is

In a Delta ABC; if 2/_A=3/_B=6/_C Determine /_A;/_B and /_C

In a triangle ABC,2/_A=3/_B=6/_C. Then the smallest angle in the Delta ABC is

In a harr ABC, if 2/_A=3/_B=6/_C determine /_A,/_B and /_C.

In a ABC, if 2/_A=3/_b=6/_c, determine /_A,/_B and /_C

In a triangle ABC, if /_A=55^(@) and /_B=15^(@), then c^(2)-a^(2) is equal to

RS AGGARWAL-CONSTRUCTIONS-EXERCISE C(M.C.Q)
  1. In the given figure, /A - 50^(@), CE || BA and /ECD -60^(@). Then, ZAC...

    Text Solution

    |

  2. In /\\ABC, if /A =65^(@) and /C =85^(@), then /B = ?

    Text Solution

    |

  3. The sum of two angles of a triangle is 80^0 and their difference is...

    Text Solution

    |

  4. The sum of all angles of a quadrilateral is

    Text Solution

    |

  5. In the given figure, AB "||" CD, /OAB = 150^(@)  and /OCD = 120^(@) . ...

    Text Solution

    |

  6. In the given figure, PQ || RS, /PAB = 60^(@)  and /ACS = 100^(@) . The...

    Text Solution

    |

  7. In the given figure, AB | CD || EF, /ABG = 110^(@) , /GCD = 100^(@)  a...

    Text Solution

    |

  8. Which of the following sentences are statements? In case of a statemen...

    Text Solution

    |

  9. The diagonals of a rhombus

    Text Solution

    |

  10. In /\\ABC, /B = 90^(@) , AB = 5 cm and AC = 13 cm. Then, BC = ?

    Text Solution

    |

  11. In a △ABC it is given that /B = 37^(@)  and /C =29^(@) . Then, /A = ?

    Text Solution

    |

  12. The angles of a triangle are in the ratio 2:3: 7. The measure of the l...

    Text Solution

    |

  13. In a triangleABC, if 2 /A = 3 /B = 6/C, then /B = ?

    Text Solution

    |

  14. In a /\\ABC, if /A + /B = 65^(@)  and /B + /C = 140^(@) . Then, /B = ?

    Text Solution

    |

  15. In a /\ABC, /A - /B = 33^(@)  and /B-/C = 18^(@) . Then, /B = ?

    Text Solution

    |

  16. The angles of a triangle are (3x)^(@), (2x-7)^(@) and (4x-11)^(@). The...

    Text Solution

    |

  17. /\ ABC is right-angled at A. If AB = 24 cm and AC = 7 cm, then BC = ?

    Text Solution

    |

  18. A ladder is placd in such a way that its foot is a distance of 15 m fr...

    Text Solution

    |

  19. Two poles of height 6m and 11m stand vertically upright on a plane g...

    Text Solution

    |

  20. /\ ABC is an isosceles triangle with /C = 90^(@) and AC = 5 cm. Then, ...

    Text Solution

    |