The areas of two similar octagons are \( 9 \mathrm{~m}^{2} \) and \( 25 \mathrm{~m}^{2} \). What is the scale factor of their side lengths? [?]: [ ]

7a somma dei raggi di due circonferenze misura 15 cm e uno è i \( \frac{2}{3} \) dell'altro. Determina la lunghez- za delle due circonferenze. \[ [12 \pi \mathrm{~cm} \approx 37,68 \mathrm{~cm} \mathrm{e} 18 \pi \mathrm{~cm} \approx 56,52 \mathrm{cm]} \]

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

50. Ten distinct lines lie in the same plane. No pair of these lines is parallel to each other, and no more than two of the lines intersect at any one point. How many poins lie on more than one of these ten lines? (A) 10 (B) 36 (D) 45 (D) 55 (E) 100

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

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