Answer:
[tex]\sf sec(D)=\sqrt{2}[/tex]
Step-by-step explanation:
First, find the length of the hypotenuse using Pythagoras' Theorem:
[tex]a^2+b^2=c^2[/tex]
(where a and b are the legs, and c is the hypotenuse, of a right triangle)
Given:
- [tex]a=4\sqrt{10}[/tex]
- [tex]b=4\sqrt{10}[/tex]
Subtituting the given values into the formula and solving for c:
[tex]\implies (4\sqrt{10})^2+(4\sqrt{10})^2=c^2[/tex]
[tex]\implies 160+160=c^2[/tex]
[tex]\implies c^2=320[/tex]
[tex]\implies c=\sqrt{320}[/tex]
[tex]\implies c=8\sqrt{5}[/tex]
Therefore, the hypotenuse is [tex]\sf 8\sqrt{5}[/tex]
Secant of an angle in a right triangle:
[tex]\sf \sec(\theta)=\dfrac{\sf hypotenuse}{\sf adjacent\:side}[/tex]
Given:
- [tex]\theta[/tex] = D
- hypotenuse = [tex]\sf 8\sqrt{5}[/tex]
- adjacent side = [tex]\sf 4\sqrt{10}[/tex]
Substituting the given values into the formula:
[tex]\implies \sf \sec(D)=\dfrac{8\sqrt{5}}{4\sqrt{10}}=\sqrt2}[/tex]