Answer:
∠4 = 104
Step-by-step explanation:
Angles 3 and 4 are supplementary (add up to the sum of 180°) so we can say:
∠3 + ∠4 = 180
76 + ∠4 = 180
∠4 = 180 - 76
Hope this helps!
20/29
sin θ = 21/29
Use Pythagorean identity:
sin² θ + cos² θ = 1
(21/29)² + cos² θ = 1
441/841 + cos² θ = 1
cos² θ = 400/841
cos θ = ±20/29
Since 0° < θ < 90°, cos θ > 0. So cos θ = 20/29.
28/7
