How do you write in simplest radical form the coordinates of point A if A is on the terminal side of angle in standard position whose degree measure is theta: OA=15, theta=135^circ?

1 Answer
Nov 17, 2017

The coordinates are (15/sqrt(2),15/sqrt(2))

Explanation:

Start by making a reference triangle for your angle.

![Desmos.com and MS Paint](useruploads.socratic.org)

The inner angle of the right triangle is 180-135=45 degrees. The side opposite the 45 degree angle is the y coordinate, and the side adjacent to the 45 degree angle is the x coordinate.

The properties of a 45-45-90 right triangle are

![Dummies.com](useruploads.socratic.org)

So the hypotenuse is 15=ysqrt(2). We can solve this by dividing both sides by sqrt(2).

x=15/sqrt(2) and y=15/sqrt(2).

Thus, the coordinates are (15/sqrt(2),15/sqrt(2))