Answer:
45
Step-by-step explanation:
Triangles equal up to 180 degrees therefore you do the following to solve this equation. So you have 80 and 55. So you add 80 to 55 and you get 135. Now you subtract 180 by 135 and that equals 45. So x=45. I will write it out as well.
55+80=135
180-135=45
x=45
To check.
80+55+45=180
36 and 12
36+12=48 and 36-12=24
Given that the point (12,-5) which takes the form (x,y), This implies that:
opposite=-5
adjacent=12
thus using using Pythagorean theorem, the hypotenuse will be:
c^2=a^2+b^2
plugging the values we obtain:
c^2=(12)^2+(-5)^2
c^2=144+15
c^2=169
thus
c=13
but
cos θ=adjacent/ hypotenuse
therefore:
cos θ=12/13
Answer is option . D
