I've tried a billion times to answer this question, and I keep getting (2√ 3)/3
I've been using the 30,60,90 degree right triangle, whereby the sides are 1,2,√ 3

An equation of the terminal side of an angle theta in standard position is given along with the quadrant of the angle theta. Find the indicated trigonometric function value of theta. Do not use a calculator.

The terminal side of theta is in quadrant I and lies on the line -2x+y=0
Find Sin theta.

The answer is (2√5)/5
But how?

Wow, okay the question came out totally messed up, let me fix it.


I've tried a billion times to answer this question, and I keep getting (2 square root of 3)/3
I've been using the 30,60,90 degree right triangle, whereby the sides are 1,2,square root of 3

An equation of the terminal side of an angle theta in standard position is given along with the quadrant of the angle theta. Find the indicated trigonometric function value of theta. Do not use a calculator.

The terminal side of theta is in quadrant I and lies on the line -2x+y=0
Find Sin theta.

The answer is (2 square root of 5)/5
but how?

Never mind I figured out why that's the answer.