The given figure is a circular cylinder, and the pencil represents its diagonal.
We know that
• The pencil is 17 cm.
,
• The height is 15 cm.
Notice that the pencil, the height of the cup, and its width form a right rectangle.
We use Pythagorean's Theorem to find the width w. Remember that this theorem relates the square hypotenuse with the sum of the square of the legs.
[tex](17)^2=(15)^2+w^2[/tex]
Let's solve for w
[tex]\begin{gathered} 289-225=w^2 \\ w^2=64 \\ w=\sqrt[]{64} \\ w=8 \end{gathered}[/tex]
Therefore, the width is 8 centimeters long.
