In a `Delta PQR`, N is a point on PR, such that QN`bot`PR. If PN`cdot`NR=`QN^(2)`, then prove that `anglePQR=90^(@)`.

Explanation

To prove that angle PQR = 90 degrees in triangle PQR, where N is a point on PR such that QN is perpendicular to PR and PN * NR = QN², we can follow these steps:

### Step-by-Step Solution:

1. **Draw the Triangle**:
Begin by sketching triangle PQR with point N on line segment PR such that QN is perpendicular to PR. Label the angles as follows: let angle PQN = A and angle NQR = B.

**Hint**: Visualizing the triangle and the perpendicular line helps in understanding the relationships between the angles.
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