3. prendre la valcur de \( \pi=3,14 \). a) Calculer l'aire et le périmètre d'un disque de 76 cm de diamétre. b) L'aire d'un disque mesure \( 3846,5 \mathrm{~cm}^{2} \). Combien mesure son rayon? \( \frac{2}{3.14 .76}=238 \cdot 64 \mathrm{~cm} \)

3. If the distance between the point \( (a, 2) \) and \( (3,1) \) be 8 , then a \( = \) ? \( \begin{array}{llll}\text { (1) } 2 \pm 3 \sqrt{15} & \text { (2) } 2-3 \sqrt{15} & \text { (3) } 3 \pm 2 \sqrt{15} & \text { (4) None of these }\end{array} \)

Een afstand van 63 km wordt op een kaart voorgesteld door \( 2,1 \mathrm{~cm} \). Op welke schaal is deze kaart getekend?

Find the equations of the two straight lines which pass through the point \( (-3,2) \) and parallel to the two axes.

The volume of a cone varies jointly as the height and the square of the radius. Suppose a cone has the measurements \( V=5425.92 \) cubic meters, \( r=12 \) meters and \( h=36 \) meters. Step 1 of 2 : Find the constant of proportionality \( k \), rounded to two decimal places if necessary, and use it to write an equation that models the relationship.

the adjacent side of a right angle riangle is 8 cm , and the ypotenuse is 10 cm , what is the ength of the opposite side? 10 cm 6 cm 9 cm 8 cm