Respuesta :
[tex]d=a \sqrt{2} \\ \\ a \sqrt{2} =18 \\ \\ a= \frac{18}{ \sqrt{2} } = \frac{18 \sqrt{2} }{2}=9 \sqrt{2} \\ \\ x= \frac{a}{2} \\ \\ x= \frac{9 \sqrt{2} }{2} [/tex]
Answer:
C
Step-by-step explanation:
The Square ABCD inscribed in a circle is shown in the picture attached.
- The diagonal is broken down into two 9 cm parts as shown.
- We let [tex]y[/tex] be the length of the apothem [line from center of square to midpoint of side].
- Also, we let [tex]x[/tex] be half the length of the side of the square.
- Since square, [tex]x[/tex] and [tex]y[/tex] are equal
Let's find the side length of the square using pythagorean theorem:
[tex](Side Length)^{2}+(Side Length)^{2}=18^{2}\\2SideLength^{2}=324\\SideLength^{2}=162\\SideLength=\sqrt{162}[/tex]
Since, [tex]x[/tex] is HALF of SIDE LENGTH, [tex]x[/tex] is:
[tex]x=\frac{\sqrt{162}}{2}\\x=\frac{\sqrt{81}*\sqrt{2}}{2}\\x=\frac{9\sqrt{2}}{2}[/tex]
Since, [tex]x[/tex] and [tex]y[/tex] are equal, we can say [tex]y=\frac{9\sqrt{2}}{2}[/tex]
Apothem's length is [tex]\frac{9\sqrt{2}}{2}[/tex]. Answer choice C is right.
