Can someone plz me in question 11 u

Which geometric principle is used to justify the construction below?

The value of cos 30° is the same as which of the following?

4. (10.03 mc) the equation of line cd is y = −2x − 2. write an equation of a line parallel to line cd in slope-intercept form that contains point (4, 5). (4 points) y = −2x + 13 y = negative 1 over 2 x + 7 y = negative 1 over 2 x + 3 − 2x − 3