Answer:
In standard position, the terminal ray of angle A passes through the point (10,-4) on the coordinate plane. The distance of the point (10, -4) from the origin (0,0) is the hypotenuse of a right triangle. The horizontal distance of the point from the y-axis is the x-coordinate, which is 10, and the vertical distance of the point from the x-axis is the y-coordinate, which is -4.
The secant of an angle is the ratio of the hypotenuse (c) to the adjacent side (a). In this case, the hypotenuse is the distance between the point (10, -4) and the origin (0,0) and the adjacent side is the x-coordinate which is 10.
So sec(A) = c/a = √(10² + (-4)²)/10 = √(100+16)/10 = √116/10 = √29/5
So sec(A) = √29/5 which is the simplified form.