The line segment with endpoints (−20, 21) and (0, 0) is graphed on the standard coordinate plane and makes an angle, Θ, with respect to the x axis. What is cos Θ?
1 Answer
Jun 2, 2018
Explanation:
#"the point "(-20,21)" is in the second quadrant"#
#"where "costheta<0#
#"calculate the hypotenuse of the right triangle with"#
#"sides of length 20 and 21"#
#"using "color(blue)"Pythagoras' theorem ""with hypotenuse h"#
#h=sqrt(20^2+21^2)=sqrt841=29#
#costheta="adjacent"/"hypotenuse"=-20/29#
