Un cuadrado tiene un area de 36 cm ¿Cuánto mide suladg? \( \begin{array}{ll}\text { (a) } 6 \mathrm{~cm} \text { b) } 9 \mathrm{~cm} \text { di } & \mathrm{cm} \text { d) } 18 \mathrm{~cm}\end{array} \)

2] \( A B C D \) is aparallelogram, \( m(\angle A)+m(\angle C)=200^{\circ} \), then \( m(\angle B)=\ldots(50,80,100,160) \)

(a) Find the area of the \( \triangle P Q R \). (b) Find \( Q M \). 9. In the given figure \( D L \) and \( B M \) are the heights corresponding to sides \( A B \) and \( A D \) respectively of parallelogram \( A B C D \). If the area of parallelogram is \( 300 \mathrm{~cm}^{2}, A B=30 \mathrm{~cm} \) and \( A D=20 \mathrm{~cm} \). Find the length of \( B M \) and \( D L \).

47. The measure, in degrees, of each interior angle of a regular polygon with \( n \) sides is given by \( \frac{(n-2) \mid 80}{n} \). What is the sum of the measures of the interior angles of a regular octagon?

Calcola la lunghezza di una circoner tro 8 cm , approssimando \( \pi \) ai centesimi.

3] (a) If the distance between the point \( (a, 7) \) and the point \( (0,-5) \) equals 13 length units find the value of a