Question

Find sin theta if theta is an angle in standard position and the point with coordinates (3, -4) lies on the terminal side of an angle.

Answer 1

Answer:

$\sin \theta=-\frac{4}{5}$

Step-by-step explanation:

Given:

Angle is in standard position which means the starting ray is at the origin. The terminal side has coordinates (3, -4).

So, the 'x' value is 3 and 'y' value id -4.

Using Pythagoras Theorem, we find the hypotenuse.

Hypotenuse = $\sqrt{3^2+(-4)^2}=\sqrt{9+16}=\sqrt{25}=5$

Now, using the sine ratio for the angle, we have

$\sin \theta=\frac{Opposite}{Hypotenuse}\\\sin \theta=\frac{-4}{5}\\\sin \theta=-\frac{4}{5}$

Therefore, the value of $\sin \theta$ is $-\frac{4}{5}$.

The value is negative as the point (3, -4) lies in the fourth quadrant and sine ratio is negative in the fourth quadrant,