A curtain panel is 8 feet long and has a perimeter of 26 feet. How wide is the curtain panel?

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?

2 complementary angles have the sum of ............... \( 360^{\circ} \) B. \( 90^{\circ} \) C. \( 180^{\circ} \) D. \( 60^{\circ} \)

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. \[ [12 \pi \mathrm{~cm} \approx 37,68 \mathrm{~cm} \mathrm{e} 18 \pi \mathrm{~cm} \approx 56,52 \mathrm{cm]} \]

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

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