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In a triangle PQR , angle P = 110^(@) , ...

In a `triangle PQR , angle P = 110^(@) `, PQ = PR . Find `angle Q and angle R `

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To solve the problem, we need to find the angles Q and R in triangle PQR, where angle P is given as 110 degrees and sides PQ and PR are equal. ### Step-by-Step Solution: 1. **Identify Given Information**: - Angle P = 110 degrees - PQ = PR (which indicates that triangle PQR is isosceles) 2. **Use the Isosceles Triangle Property**: - Since PQ = PR, the angles opposite these sides (angle Q and angle R) must be equal. Therefore, we can say: \[ \text{Angle Q} = \text{Angle R} \] 3. **Apply the Angle Sum Property of a Triangle**: - The sum of the angles in any triangle is 180 degrees. Therefore, we can write: \[ \text{Angle P} + \text{Angle Q} + \text{Angle R} = 180^\circ \] - Substituting the known values: \[ 110^\circ + \text{Angle Q} + \text{Angle R} = 180^\circ \] 4. **Substitute Angle Q for Angle R**: - Since Angle Q = Angle R, we can denote both as Q: \[ 110^\circ + Q + Q = 180^\circ \] \[ 110^\circ + 2Q = 180^\circ \] 5. **Solve for Q**: - Rearranging the equation gives: \[ 2Q = 180^\circ - 110^\circ \] \[ 2Q = 70^\circ \] - Dividing by 2: \[ Q = \frac{70^\circ}{2} = 35^\circ \] 6. **Find Angle R**: - Since Angle Q = Angle R, we have: \[ \text{Angle R} = 35^\circ \] ### Final Answer: - Angle Q = 35 degrees - Angle R = 35 degrees
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Knowledge Check

  • In the figure above angle SPT = 60^(@) and PQ = PR " Find " angle PQR

    A
    `50^(@)`
    B
    `45^(@)`
    C
    `60^(@)`
    D
    `55^(@)`
  • In a triangle PQR , angle Q = 90^(@) . If PQ = 12 cm " and " QR = 5 cm, then what is the radius ( in cm ) of the circumcircle of the triangle ?

    A
    5
    B
    6
    C
    `6. 5`
    D
    `6 sqrt 2`
  • I is the incentre of a triangle PQR and angle = 107^@ then find the value angle P .

    A
    56°
    B
    34°
    C
    26°
    D
    42°
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    In triangle PQR , angle Q= 85^@ and angle R= 65^@ . Points S and T are on the sides PQ and PR, respectively such that angle STR = 95^@ , then the ratio of QR and ST is 9:5. If PQ=21.6 cm, then the length of PT is: triangle PQR में, angle Q= 85^@ तथा angle R= 65^@ है | बिंदु S तथा T क्रमशः भुजाओं PQ और PR पर इस तरह स्थित है कि angle STR = 95^@ है | QR तथा ST का अनुपात 9 : 5 है | यदि PQ =21.6 सेमी है, तो PT की लंबाई ज्ञात करें |

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