Answer: see proof below
<u>Step-by-step explanation:</u>
Use the Sum & Difference Identity: tan (A - B) = (tanA - tanB)/(1 + tanA tanB)
Use the Half-Angle Identity: tan (A/2) = (1 - cosA)/(sinA)
Use the Unit Circle to evaluate tan (π/4) = 1
Use Pythagorean Identity: cos²A + sin²A = 1
<u>Proof LHS → RHS</u>








= cos A
LHS = RHS: cos A = cos A 
Step-by-step explanation:
20 mails in 1/4 day (0.25 day)
-> 1 day = 20/0.25 = 80 emails
Answer:
We can see that it is an isosceles triangle so base angles are equal.
Step-by-step explanation:
x + x + 56 = 180
2x = 180 - 56
2x = 124
x = 124/2
Therefore x = 62.
Answer:
1. Given
2. AAS
3. Reflexive
4. Definition of perpendicular
5. Definition of angle bisector
6. CPCTE