I'm so confused what do you need help with?
Answer:
Algebraic expression ;

Step-by-step explanation:
4 is subtracted from r means the same as r decreased by 4
Subtracted = -

Answer:
≈ 68.2°
Step-by-step explanation:
tan X= 20/8
tan X= 2.5
x= tan ⁻¹ 2.5
x ≈ 68.2°